\[ \left \{\text {a11} x''(t)+\text {a12} y''(t)+\text {b11} x'(t)+\text {b12} y'(t)+\text {c11} x(t)+\text {c12} y(t)=0,\text {a21} x''(t)+\text {a22} y''(t)+\text {b21} x'(t)+\text {b22} y'(t)+\text {c21} x(t)+\text {c22} y(t)=0\right \} \] ✓ Mathematica : cpu = 0.4648 (sec), leaf count = 6816
\[\left \{\left \{x(t)\to (\text {a11} \text {a22}-\text {a12} \text {a21}) c_4 \text {RootSum}\left [\text {$\#$1}^4-\text {a22} \text {b11} \text {$\#$1}^3+\text {a21} \text {b12} \text {$\#$1}^3+\text {a12} \text {b21} \text {$\#$1}^3-\text {a11} \text {b22} \text {$\#$1}^3+\text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}^2-\text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}^2-\text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}^2+\text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}^2+\text {a11} \text {a22}^2 \text {c11} \text {$\#$1}^2-\text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}^2+\text {a12} \text {a21}^2 \text {c12} \text {$\#$1}^2-\text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}^2+\text {a12}^2 \text {a21} \text {c21} \text {$\#$1}^2-\text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}^2-\text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}^2+\text {a11}^2 \text {a22} \text {c22} \text 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\text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c12} \text {c21}-3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c12} \text {c21}-\text {a12}^3 \text {a21}^3 \text {c11} \text {c22}+\text {a11}^3 \text {a22}^3 \text {c11} \text {c22}-3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c11} \text {c22}+3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c11} \text {c22}\& ,\frac {\text {a21} \text {c22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {a12}^2-\text {a21} \text {a22} \text {c12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {a12}-\text {a11} \text {a22} \text {c22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {a12}+\text {b22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1} \text {a12}+\text {a11} \text {a22}^2 \text {c12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}-\text {a22} \text {b12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}}{4 \text {$\#$1}^3-3 \text {a22} \text {b11} \text {$\#$1}^2+3 \text {a21} \text {b12} \text {$\#$1}^2+3 \text {a12} \text {b21} \text {$\#$1}^2-3 \text {a11} \text {b22} \text {$\#$1}^2+2 \text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}-2 \text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}-2 \text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22}^2 \text {c11} \text {$\#$1}-2 \text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}+2 \text {a12} \text {a21}^2 \text {c12} \text {$\#$1}-2 \text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}+2 \text {a12}^2 \text {a21} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}+2 \text {a11}^2 \text {a22} \text {c22} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b22} \text {c11}-\text {a11}^2 \text {a22}^2 \text {b22} \text {c11}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22}}\& \right ]+(\text {a12} \text {a21}-\text {a11} \text {a22}) c_3 \text {RootSum}\left [\text {$\#$1}^4-\text {a22} \text {b11} \text {$\#$1}^3+\text {a21} \text {b12} \text {$\#$1}^3+\text {a12} \text {b21} \text {$\#$1}^3-\text {a11} 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{a21}^2 \text {b21} \text {c12} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22} \text {$\#$1}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22} \text {$\#$1}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22} \text {$\#$1}+\text {a12}^3 \text {a21}^3 \text {c12} \text {c21}-\text {a11}^3 \text {a22}^3 \text {c12} \text {c21}+3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c12} \text {c21}-3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c12} \text {c21}-\text {a12}^3 \text {a21}^3 \text {c11} \text {c22}+\text {a11}^3 \text {a22}^3 \text {c11} \text 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{c11}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22}}\& \right ]+(\text {a12} \text {a21}-\text {a11} \text {a22}) c_2 \text {RootSum}\left [\text {$\#$1}^4-\text {a22} \text {b11} \text {$\#$1}^3+\text {a21} \text {b12} \text {$\#$1}^3+\text {a12} \text {b21} \text {$\#$1}^3-\text {a11} \text {b22} \text {$\#$1}^3+\text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}^2-\text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}^2-\text {a12} \text {a21} \text {b11} \text {b22} \text 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\text {a21}^2 \text {b12} \text {c21} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22} \text {$\#$1}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22} \text {$\#$1}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22} \text {$\#$1}+\text {a12}^3 \text {a21}^3 \text {c12} \text {c21}-\text {a11}^3 \text {a22}^3 \text {c12} \text {c21}+3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c12} \text {c21}-3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c12} \text {c21}-\text {a12}^3 \text {a21}^3 \text {c11} \text {c22}+\text {a11}^3 \text {a22}^3 \text {c11} \text {c22}-3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c11} \text {c22}+3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c11} \text {c22}\& ,\frac {\text {a22} \text {c22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {a11}^2-\text {a21} \text {a22} \text {c12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {a11}-\text {a12} \text {a21} \text {c22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {a11}-\text {b22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1} \text {a11}+\text {a12} \text {a21}^2 \text {c12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}+e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^2+\text {a21} \text {b12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}}{4 \text {$\#$1}^3-3 \text {a22} \text {b11} \text {$\#$1}^2+3 \text {a21} \text {b12} \text {$\#$1}^2+3 \text {a12} \text {b21} \text {$\#$1}^2-3 \text {a11} \text {b22} \text {$\#$1}^2+2 \text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}-2 \text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}-2 \text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22}^2 \text {c11} \text {$\#$1}-2 \text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}+2 \text {a12} \text {a21}^2 \text {c12} \text {$\#$1}-2 \text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}+2 \text {a12}^2 \text {a21} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}+2 \text {a11}^2 \text {a22} \text {c22} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b22} \text {c11}-\text {a11}^2 \text {a22}^2 \text {b22} \text {c11}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22}}\& \right ]+c_1 \text {RootSum}\left [\text {$\#$1}^4-\text {a22} \text {b11} \text {$\#$1}^3+\text {a21} \text {b12} \text {$\#$1}^3+\text {a12} \text {b21} \text {$\#$1}^3-\text {a11} \text {b22} \text {$\#$1}^3+\text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}^2-\text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}^2-\text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}^2+\text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}^2+\text {a11} \text {a22}^2 \text {c11} \text {$\#$1}^2-\text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}^2+\text {a12} \text {a21}^2 \text {c12} \text {$\#$1}^2-\text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}^2+\text {a12}^2 \text {a21} \text {c21} \text {$\#$1}^2-\text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}^2-\text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}^2+\text {a11}^2 \text {a22} \text {c22} \text {$\#$1}^2-\text {a12}^2 \text {a21}^2 \text {b22} \text {c11} \text {$\#$1}-\text {a11}^2 \text {a22}^2 \text {b22} \text {c11} \text {$\#$1}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22} \text {$\#$1}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22} \text {$\#$1}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22} \text {$\#$1}+\text {a12}^3 \text {a21}^3 \text {c12} \text {c21}-\text {a11}^3 \text {a22}^3 \text {c12} \text {c21}+3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c12} \text {c21}-3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c12} \text {c21}-\text {a12}^3 \text {a21}^3 \text {c11} \text {c22}+\text {a11}^3 \text {a22}^3 \text {c11} \text {c22}-3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c11} \text {c22}+3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c11} \text {c22}\& ,\frac {e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^3-\text {a22} \text {b11} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^2+\text {a21} \text {b12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^2+\text {a12} \text {b21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^2-\text {a11} \text {b22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^2+\text {a12} \text {a21} \text {b12} \text {b21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}-\text {a11} \text {a22} \text {b12} \text {b21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}-\text {a12} \text {a21} \text {b11} \text {b22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}+\text {a11} \text {a22} \text {b11} \text {b22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}+\text {a12} \text {a21}^2 \text {c12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}-\text {a11} \text {a21} \text {a22} \text {c12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}-\text {a11} \text {a12} \text {a21} \text {c22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}+\text {a11}^2 \text {a22} \text {c22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}}{4 \text {$\#$1}^3-3 \text {a22} \text {b11} \text {$\#$1}^2+3 \text {a21} \text {b12} \text {$\#$1}^2+3 \text {a12} \text {b21} \text {$\#$1}^2-3 \text {a11} \text {b22} \text {$\#$1}^2+2 \text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}-2 \text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}-2 \text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22}^2 \text {c11} \text {$\#$1}-2 \text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}+2 \text {a12} \text {a21}^2 \text {c12} \text {$\#$1}-2 \text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}+2 \text {a12}^2 \text {a21} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}+2 \text {a11}^2 \text {a22} \text {c22} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b22} \text {c11}-\text {a11}^2 \text {a22}^2 \text {b22} \text {c11}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22}}\& \right ],y(t)\to (\text {a12} \text {a21}-\text {a11} \text {a22}) c_2 \text {RootSum}\left [\text {$\#$1}^4-\text {a22} \text {b11} 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\text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22} \text {$\#$1}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22} \text {$\#$1}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22} \text {$\#$1}+\text {a12}^3 \text {a21}^3 \text {c12} \text {c21}-\text {a11}^3 \text {a22}^3 \text {c12} \text {c21}+3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c12} \text {c21}-3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c12} \text 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{$\#$1}^3+3 \text {a22} \text {b11} \text {$\#$1}^2-3 \text {a21} \text {b12} \text {$\#$1}^2-3 \text {a12} \text {b21} \text {$\#$1}^2+3 \text {a11} \text {b22} \text {$\#$1}^2-2 \text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}+2 \text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}+2 \text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}-2 \text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}-2 \text {a11} \text {a22}^2 \text {c11} \text {$\#$1}+2 \text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}-2 \text {a12} \text {a21}^2 \text {c12} \text {$\#$1}+2 \text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}-2 \text {a12}^2 \text {a21} \text {c21} \text {$\#$1}+2 \text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}+2 \text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}-2 \text {a11}^2 \text {a22} \text {c22} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b22} \text {c11}+\text {a11}^2 \text {a22}^2 \text {b22} \text {c11}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11}-\text {a12}^2 \text {a21}^2 \text {b21} \text {c12}-\text {a11}^2 \text {a22}^2 \text {b21} \text {c12}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12}-\text {a12}^2 \text {a21}^2 \text {b12} \text {c21}-\text {a11}^2 \text {a22}^2 \text {b12} \text {c21}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21}+\text {a12}^2 \text {a21}^2 \text {b11} \text {c22}+\text {a11}^2 \text {a22}^2 \text {b11} \text {c22}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22}}\& \right ]+(\text {a11} \text {a22}-\text {a12} \text {a21}) c_1 \text {RootSum}\left [\text {$\#$1}^4-\text {a22} \text {b11} \text {$\#$1}^3+\text {a21} \text {b12} \text {$\#$1}^3+\text {a12} \text {b21} \text {$\#$1}^3-\text {a11} \text {b22} \text {$\#$1}^3+\text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}^2-\text {a11} \text {a22} \text {b12} \text {b21} 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{c11} \text {c22}\& ,\frac {\text {a12} \text {a21} \text {b21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {c11}-\text {a11} \text {a22} \text {b21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {c11}+\text {a21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1} \text {c11}-\text {a12} \text {a21} \text {b11} \text {c21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}+\text {a11} \text {a22} \text {b11} \text {c21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}-\text {a11} \text {c21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}}{4 \text {$\#$1}^3-3 \text {a22} \text {b11} \text {$\#$1}^2+3 \text {a21} \text {b12} \text {$\#$1}^2+3 \text {a12} \text {b21} \text {$\#$1}^2-3 \text {a11} \text {b22} \text {$\#$1}^2+2 \text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}-2 \text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}-2 \text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22}^2 \text {c11} \text {$\#$1}-2 \text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}+2 \text {a12} \text {a21}^2 \text {c12} \text {$\#$1}-2 \text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}+2 \text {a12}^2 \text {a21} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}+2 \text {a11}^2 \text {a22} \text {c22} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b22} \text {c11}-\text {a11}^2 \text {a22}^2 \text {b22} \text {c11}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22}}\& \right ]+(\text {a12} \text {a21}-\text {a11} \text {a22}) c_4 \text {RootSum}\left [\text {$\#$1}^4-\text {a22} \text {b11} \text {$\#$1}^3+\text {a21} \text {b12} \text {$\#$1}^3+\text {a12} \text {b21} \text {$\#$1}^3-\text {a11} \text {b22} \text {$\#$1}^3+\text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}^2-\text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}^2-\text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}^2+\text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}^2+\text {a11} \text {a22}^2 \text {c11} \text {$\#$1}^2-\text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}^2+\text {a12} \text {a21}^2 \text {c12} \text {$\#$1}^2-\text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}^2+\text {a12}^2 \text {a21} \text {c21} \text {$\#$1}^2-\text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}^2-\text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}^2+\text {a11}^2 \text {a22} \text {c22} \text {$\#$1}^2-\text {a12}^2 \text {a21}^2 \text {b22} \text {c11} \text {$\#$1}-\text {a11}^2 \text {a22}^2 \text {b22} \text {c11} \text {$\#$1}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22} \text {$\#$1}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22} \text {$\#$1}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22} \text {$\#$1}+\text {a12}^3 \text {a21}^3 \text {c12} \text {c21}-\text {a11}^3 \text {a22}^3 \text {c12} \text {c21}+3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c12} \text {c21}-3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c12} \text {c21}-\text {a12}^3 \text {a21}^3 \text {c11} \text {c22}+\text {a11}^3 \text {a22}^3 \text {c11} \text {c22}-3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c11} \text {c22}+3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c11} \text {c22}\& ,\frac {\text {a21} \text {c21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {a12}^2-\text {a21} \text {a22} \text {c11} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {a12}-\text {a11} \text {a22} \text {c21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {a12}+\text {b21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1} \text {a12}+\text {a11} \text {a22}^2 \text {c11} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}+e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^2-\text {a22} \text {b11} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}}{4 \text {$\#$1}^3-3 \text {a22} \text {b11} \text {$\#$1}^2+3 \text {a21} \text {b12} \text {$\#$1}^2+3 \text {a12} \text {b21} \text {$\#$1}^2-3 \text {a11} \text {b22} \text {$\#$1}^2+2 \text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}-2 \text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}-2 \text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22}^2 \text {c11} \text {$\#$1}-2 \text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}+2 \text {a12} \text {a21}^2 \text {c12} \text {$\#$1}-2 \text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}+2 \text {a12}^2 \text {a21} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}+2 \text {a11}^2 \text {a22} \text {c22} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b22} \text {c11}-\text {a11}^2 \text {a22}^2 \text {b22} \text {c11}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22}}\& \right ]+c_3 \text {RootSum}\left [\text {$\#$1}^4-\text {a22} \text {b11} \text {$\#$1}^3+\text {a21} \text {b12} \text {$\#$1}^3+\text {a12} \text {b21} \text {$\#$1}^3-\text {a11} \text {b22} \text {$\#$1}^3+\text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}^2-\text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}^2-\text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}^2+\text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}^2+\text {a11} \text {a22}^2 \text {c11} \text {$\#$1}^2-\text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}^2+\text {a12} \text {a21}^2 \text {c12} \text {$\#$1}^2-\text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}^2+\text {a12}^2 \text {a21} \text {c21} \text {$\#$1}^2-\text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}^2-\text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}^2+\text {a11}^2 \text {a22} \text {c22} \text {$\#$1}^2-\text {a12}^2 \text {a21}^2 \text {b22} \text {c11} \text {$\#$1}-\text {a11}^2 \text {a22}^2 \text {b22} \text {c11} \text {$\#$1}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12} \text {$\#$1}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21} \text {$\#$1}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22} \text {$\#$1}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22} \text {$\#$1}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22} \text {$\#$1}+\text {a12}^3 \text {a21}^3 \text {c12} \text {c21}-\text {a11}^3 \text {a22}^3 \text {c12} \text {c21}+3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c12} \text {c21}-3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c12} \text {c21}-\text {a12}^3 \text {a21}^3 \text {c11} \text {c22}+\text {a11}^3 \text {a22}^3 \text {c11} \text {c22}-3 \text {a11}^2 \text {a12} \text {a21} \text {a22}^2 \text {c11} \text {c22}+3 \text {a11} \text {a12}^2 \text {a21}^2 \text {a22} \text {c11} \text {c22}\& ,\frac {e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^3-\text {a22} \text {b11} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^2+\text {a21} \text {b12} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^2+\text {a12} \text {b21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^2-\text {a11} \text {b22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}^2+\text {a12} \text {a21} \text {b12} \text {b21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}-\text {a11} \text {a22} \text {b12} \text {b21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}-\text {a12} \text {a21} \text {b11} \text {b22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}+\text {a11} \text {a22} \text {b11} \text {b22} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}+\text {a11} \text {a22}^2 \text {c11} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}-\text {a12} \text {a21} \text {a22} \text {c11} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}+\text {a12}^2 \text {a21} \text {c21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}-\text {a11} \text {a12} \text {a22} \text {c21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b22} \text {c11} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}-\text {a11}^2 \text {a22}^2 \text {b22} \text {c11} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21} e^{\frac {t \text {$\#$1}}{\text {a12} \text {a21}-\text {a11} \text {a22}}}}{4 \text {$\#$1}^3-3 \text {a22} \text {b11} \text {$\#$1}^2+3 \text {a21} \text {b12} \text {$\#$1}^2+3 \text {a12} \text {b21} \text {$\#$1}^2-3 \text {a11} \text {b22} \text {$\#$1}^2+2 \text {a12} \text {a21} \text {b12} \text {b21} \text {$\#$1}-2 \text {a11} \text {a22} \text {b12} \text {b21} \text {$\#$1}-2 \text {a12} \text {a21} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22} \text {b11} \text {b22} \text {$\#$1}+2 \text {a11} \text {a22}^2 \text {c11} \text {$\#$1}-2 \text {a12} \text {a21} \text {a22} \text {c11} \text {$\#$1}+2 \text {a12} \text {a21}^2 \text {c12} \text {$\#$1}-2 \text {a11} \text {a21} \text {a22} \text {c12} \text {$\#$1}+2 \text {a12}^2 \text {a21} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a22} \text {c21} \text {$\#$1}-2 \text {a11} \text {a12} \text {a21} \text {c22} \text {$\#$1}+2 \text {a11}^2 \text {a22} \text {c22} \text {$\#$1}-\text {a12}^2 \text {a21}^2 \text {b22} \text {c11}-\text {a11}^2 \text {a22}^2 \text {b22} \text {c11}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b22} \text {c11}+\text {a12}^2 \text {a21}^2 \text {b21} \text {c12}+\text {a11}^2 \text {a22}^2 \text {b21} \text {c12}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b21} \text {c12}+\text {a12}^2 \text {a21}^2 \text {b12} \text {c21}+\text {a11}^2 \text {a22}^2 \text {b12} \text {c21}-2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b12} \text {c21}-\text {a12}^2 \text {a21}^2 \text {b11} \text {c22}-\text {a11}^2 \text {a22}^2 \text {b11} \text {c22}+2 \text {a11} \text {a12} \text {a21} \text {a22} \text {b11} \text {c22}}\& \right ]\right \}\right \}\]
✓ Maple : cpu = 0.226 (sec), leaf count = 1008
\[ \left \{ \left \{ x \left ( t \right ) =\sum _{{\it \_a}=1}^{4}{{\rm e}^{{\it RootOf} \left ( \left ( {\it a22}\,{\it a11}-{\it a21}\,{\it a12} \right ) {{\it \_Z}}^{4}+ \left ( {\it a11}\,{\it b22}-{\it a12}\,{\it b21}-{\it a21}\,{\it b12}+{\it a22}\,{\it b11} \right ) {{\it \_Z}}^{3}+ \left ( {\it a11}\,{\it c22}-{\it a12}\,{\it c21}-{\it a21}\,{\it c12}+{\it a22}\,{\it c11}+{\it b11}\,{\it b22}-{\it b12}\,{\it b21} \right ) {{\it \_Z}}^{2}+ \left ( {\it b11}\,{\it c22}-{\it b12}\,{\it c21}-{\it b21}\,{\it c12}+{\it b22}\,{\it c11} \right ) {\it \_Z}+{\it c11}\,{\it c22}-{\it c12}\,{\it c21},{\it index}={\it \_a} \right ) t}}{\it \_C}_{{{\it \_a}}},y \left ( t \right ) ={\frac { \left ( \left ( -{\it a21}\,{\it c22}+{\it b21}\,{\it b22} \right ) {{\it a12}}^{2}+ \left ( \left ( {\it a11}\,{\it c22}+{\it a21}\,{\it c12}-{\it b11}\,{\it b22}-{\it b12}\,{\it b21} \right ) {\it a22}-{{\it b22}}^{2}{\it a11}+{\it b22}\,{\it a21}\,{\it b12} \right ) {\it a12}+ \left ( \left ( -{\it a11}\,{\it c12}+{\it b11}\,{\it b12} \right ) {\it a22}+{\it b22}\,{\it a11}\,{\it b12}-{\it a21}\,{{\it b12}}^{2} \right ) {\it a22} \right ) \sum _{{\it \_a}=1}^{4} \left ( {\it RootOf} \left ( \left ( {\it a22}\,{\it a11}-{\it a21}\,{\it a12} \right ) {{\it \_Z}}^{4}+ \left ( {\it a11}\,{\it b22}-{\it a12}\,{\it b21}-{\it a21}\,{\it b12}+{\it a22}\,{\it b11} \right ) {{\it \_Z}}^{3}+ \left ( {\it a11}\,{\it c22}-{\it a12}\,{\it c21}-{\it a21}\,{\it c12}+{\it a22}\,{\it c11}+{\it b11}\,{\it b22}-{\it b12}\,{\it b21} \right ) {{\it \_Z}}^{2}+ \left ( {\it b11}\,{\it c22}-{\it b12}\,{\it c21}-{\it b21}\,{\it c12}+{\it b22}\,{\it c11} \right ) {\it \_Z}+{\it c11}\,{\it c22}-{\it c12}\,{\it c21},{\it index}={\it \_a} \right ) \right ) ^{2}{{\rm e}^{{\it RootOf} \left ( \left ( {\it a22}\,{\it a11}-{\it a21}\,{\it a12} \right ) {{\it \_Z}}^{4}+ \left ( {\it a11}\,{\it b22}-{\it a12}\,{\it b21}-{\it a21}\,{\it b12}+{\it a22}\,{\it b11} \right ) {{\it \_Z}}^{3}+ \left ( {\it a11}\,{\it c22}-{\it a12}\,{\it c21}-{\it a21}\,{\it c12}+{\it a22}\,{\it c11}+{\it b11}\,{\it b22}-{\it b12}\,{\it b21} \right ) {{\it \_Z}}^{2}+ \left ( {\it b11}\,{\it c22}-{\it b12}\,{\it c21}-{\it b21}\,{\it c12}+{\it b22}\,{\it c11} \right ) {\it \_Z}+{\it c11}\,{\it c22}-{\it c12}\,{\it c21},{\it index}={\it \_a} \right ) t}}{\it \_C}_{{{\it \_a}}}- \left ( {\it a22}\,{\it a11}-{\it a21}\,{\it a12} \right ) \left ( {\it a12}\,{\it b22}-{\it a22}\,{\it b12} \right ) \sum _{{\it \_a}=1}^{4} \left ( {\it RootOf} \left ( \left ( {\it a22}\,{\it a11}-{\it a21}\,{\it a12} \right ) {{\it \_Z}}^{4}+ \left ( {\it a11}\,{\it b22}-{\it a12}\,{\it b21}-{\it a21}\,{\it b12}+{\it a22}\,{\it b11} \right ) {{\it \_Z}}^{3}+ \left ( {\it a11}\,{\it c22}-{\it a12}\,{\it c21}-{\it a21}\,{\it c12}+{\it a22}\,{\it c11}+{\it b11}\,{\it b22}-{\it b12}\,{\it b21} \right ) {{\it \_Z}}^{2}+ \left ( {\it b11}\,{\it c22}-{\it b12}\,{\it c21}-{\it b21}\,{\it c12}+{\it b22}\,{\it c11} \right ) {\it \_Z}+{\it c11}\,{\it c22}-{\it c12}\,{\it c21},{\it index}={\it \_a} \right ) \right ) ^{3}{{\rm e}^{{\it RootOf} \left ( \left ( {\it a22}\,{\it a11}-{\it a21}\,{\it a12} \right ) {{\it \_Z}}^{4}+ \left ( {\it a11}\,{\it b22}-{\it a12}\,{\it b21}-{\it a21}\,{\it b12}+{\it a22}\,{\it b11} \right ) {{\it \_Z}}^{3}+ \left ( {\it a11}\,{\it c22}-{\it a12}\,{\it c21}-{\it a21}\,{\it c12}+{\it a22}\,{\it c11}+{\it b11}\,{\it b22}-{\it b12}\,{\it b21} \right ) {{\it \_Z}}^{2}+ \left ( {\it b11}\,{\it c22}-{\it b12}\,{\it c21}-{\it b21}\,{\it c12}+{\it b22}\,{\it c11} \right ) {\it \_Z}+{\it c11}\,{\it c22}-{\it c12}\,{\it c21},{\it index}={\it \_a} \right ) t}}{\it \_C}_{{{\it \_a}}}+ \left ( \left ( -{\it b21}\,{\it c22}+{\it b22}\,{\it c21} \right ) {{\it a12}}^{2}+ \left ( \left ( {\it b11}\,{\it c22}-{\it b12}\,{\it c21}+{\it b21}\,{\it c12}-{\it b22}\,{\it c11} \right ) {\it a22}-{{\it b22}}^{2}{\it b11}+{\it b22}\,{\it b21}\,{\it b12} \right ) {\it a12}+ \left ( \left ( -{\it b11}\,{\it c12}+{\it c11}\,{\it b12} \right ) {\it a22}+{\it b22}\,{\it b11}\,{\it b12}-{{\it b12}}^{2}{\it b21} \right ) {\it a22} \right ) \sum _{{\it \_a}=1}^{4}{\it RootOf} \left ( \left ( {\it a22}\,{\it a11}-{\it a21}\,{\it a12} \right ) {{\it \_Z}}^{4}+ \left ( {\it a11}\,{\it b22}-{\it a12}\,{\it b21}-{\it a21}\,{\it b12}+{\it a22}\,{\it b11} \right ) {{\it \_Z}}^{3}+ \left ( {\it a11}\,{\it c22}-{\it a12}\,{\it c21}-{\it a21}\,{\it c12}+{\it a22}\,{\it c11}+{\it b11}\,{\it b22}-{\it b12}\,{\it b21} \right ) {{\it \_Z}}^{2}+ \left ( {\it b11}\,{\it c22}-{\it b12}\,{\it c21}-{\it b21}\,{\it c12}+{\it b22}\,{\it c11} \right ) {\it \_Z}+{\it c11}\,{\it c22}-{\it c12}\,{\it c21},{\it index}={\it \_a} \right ) {{\rm e}^{{\it RootOf} \left ( \left ( {\it a22}\,{\it a11}-{\it a21}\,{\it a12} \right ) {{\it \_Z}}^{4}+ \left ( {\it a11}\,{\it b22}-{\it a12}\,{\it b21}-{\it a21}\,{\it b12}+{\it a22}\,{\it b11} \right ) {{\it \_Z}}^{3}+ \left ( {\it a11}\,{\it c22}-{\it a12}\,{\it c21}-{\it a21}\,{\it c12}+{\it a22}\,{\it c11}+{\it b11}\,{\it b22}-{\it b12}\,{\it b21} \right ) {{\it \_Z}}^{2}+ \left ( {\it b11}\,{\it c22}-{\it b12}\,{\it c21}-{\it b21}\,{\it c12}+{\it b22}\,{\it c11} \right ) {\it \_Z}+{\it c11}\,{\it c22}-{\it c12}\,{\it c21},{\it index}={\it \_a} \right ) t}}{\it \_C}_{{{\it \_a}}}-\sum _{{\it \_a}=1}^{4}{{\rm e}^{{\it RootOf} \left ( \left ( {\it a22}\,{\it a11}-{\it a21}\,{\it a12} \right ) {{\it \_Z}}^{4}+ \left ( {\it a11}\,{\it b22}-{\it a12}\,{\it b21}-{\it a21}\,{\it b12}+{\it a22}\,{\it b11} \right ) {{\it \_Z}}^{3}+ \left ( {\it a11}\,{\it c22}-{\it a12}\,{\it c21}-{\it a21}\,{\it c12}+{\it a22}\,{\it c11}+{\it b11}\,{\it b22}-{\it b12}\,{\it b21} \right ) {{\it \_Z}}^{2}+ \left ( {\it b11}\,{\it c22}-{\it b12}\,{\it c21}-{\it b21}\,{\it c12}+{\it b22}\,{\it c11} \right ) {\it \_Z}+{\it c11}\,{\it c22}-{\it c12}\,{\it c21},{\it index}={\it \_a} \right ) t}}{\it \_C}_{{{\it \_a}}} \left ( {{\it a12}}^{2}{\it c21}\,{\it c22}+ \left ( -{\it a22}\,{\it c11}\,{\it c22}-{\it a22}\,{\it c12}\,{\it c21}-{\it b12}\,{\it b22}\,{\it c21}+{{\it b22}}^{2}{\it c11} \right ) {\it a12}+{{\it a22}}^{2}{\it c11}\,{\it c12}+ \left ( {{\it b12}}^{2}{\it c21}-{\it b12}\,{\it b22}\,{\it c11} \right ) {\it a22} \right ) }{{{\it c22}}^{2}{{\it a12}}^{2}+ \left ( -2\,{\it a22}\,{\it c12}\,{\it c22}-{\it b12}\,{\it b22}\,{\it c22}+{{\it b22}}^{2}{\it c12} \right ) {\it a12}+{{\it a22}}^{2}{{\it c12}}^{2}+ \left ( {{\it b12}}^{2}{\it c22}-{\it b12}\,{\it c12}\,{\it b22} \right ) {\it a22}}} \right \} \right \} \]