2.1009   ODE No. 1009

\[ l y(x)+y''(x)=0 \] Mathematica : cpu = 0.0035488 (sec), leaf count = 28

DSolve[l*y[x] + Derivative[2][y][x] == 0,y[x],x]
 

\[\left \{\left \{y(x)\to c_1 \cos \left (\sqrt {l} x\right )+c_2 \sin \left (\sqrt {l} x\right )\right \}\right \}\] Maple : cpu = 0.014 (sec), leaf count = 21

dsolve(diff(diff(y(x),x),x)+l*y(x)=0,y(x))
 

\[y \left (x \right ) = c_{1} \sin \left (\sqrt {l}\, x \right )+c_{2} \cos \left (\sqrt {l}\, x \right )\]