3.2.8 \(\int \frac {-x^2+2 x^4}{1+2 x^2} \, dx\)

Optimal. Leaf size=25 \[ \frac {x^3}{3}-x+\frac {\tan ^{-1}\left (\sqrt {2} x\right )}{\sqrt {2}} \]

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Rubi [A]  time = 0.02, antiderivative size = 25, normalized size of antiderivative = 1.00, number of steps used = 4, number of rules used = 4, integrand size = 21, \(\frac {\text {number of rules}}{\text {integrand size}}\) = 0.190, Rules used = {1593, 459, 321, 203} \begin {gather*} \frac {x^3}{3}-x+\frac {\tan ^{-1}\left (\sqrt {2} x\right )}{\sqrt {2}} \end {gather*}

Antiderivative was successfully verified.

[In]

Int[(-x^2 + 2*x^4)/(1 + 2*x^2),x]

[Out]

-x + x^3/3 + ArcTan[Sqrt[2]*x]/Sqrt[2]

Rule 203

Int[((a_) + (b_.)*(x_)^2)^(-1), x_Symbol] :> Simp[(1*ArcTan[(Rt[b, 2]*x)/Rt[a, 2]])/(Rt[a, 2]*Rt[b, 2]), x] /;
FreeQ[{a, b}, x] && PosQ[a/b] && (GtQ[a, 0] || GtQ[b, 0])

Rule 321

Int[((c_.)*(x_))^(m_)*((a_) + (b_.)*(x_)^(n_))^(p_), x_Symbol] :> Simp[(c^(n - 1)*(c*x)^(m - n + 1)*(a + b*x^n
)^(p + 1))/(b*(m + n*p + 1)), x] - Dist[(a*c^n*(m - n + 1))/(b*(m + n*p + 1)), Int[(c*x)^(m - n)*(a + b*x^n)^p
, x], x] /; FreeQ[{a, b, c, p}, x] && IGtQ[n, 0] && GtQ[m, n - 1] && NeQ[m + n*p + 1, 0] && IntBinomialQ[a, b,
c, n, m, p, x]

Rule 459

Int[((e_.)*(x_))^(m_.)*((a_) + (b_.)*(x_)^(n_))^(p_.)*((c_) + (d_.)*(x_)^(n_)), x_Symbol] :> Simp[(d*(e*x)^(m
+ 1)*(a + b*x^n)^(p + 1))/(b*e*(m + n*(p + 1) + 1)), x] - Dist[(a*d*(m + 1) - b*c*(m + n*(p + 1) + 1))/(b*(m +
n*(p + 1) + 1)), Int[(e*x)^m*(a + b*x^n)^p, x], x] /; FreeQ[{a, b, c, d, e, m, n, p}, x] && NeQ[b*c - a*d, 0]
&& NeQ[m + n*(p + 1) + 1, 0]

Rule 1593

Int[(u_.)*((a_.)*(x_)^(p_.) + (b_.)*(x_)^(q_.))^(n_.), x_Symbol] :> Int[u*x^(n*p)*(a + b*x^(q - p))^n, x] /; F
reeQ[{a, b, p, q}, x] && IntegerQ[n] && PosQ[q - p]

Rubi steps

\begin {align*} \int \frac {-x^2+2 x^4}{1+2 x^2} \, dx &=\int \frac {x^2 \left (-1+2 x^2\right )}{1+2 x^2} \, dx\\ &=\frac {x^3}{3}-2 \int \frac {x^2}{1+2 x^2} \, dx\\ &=-x+\frac {x^3}{3}+\int \frac {1}{1+2 x^2} \, dx\\ &=-x+\frac {x^3}{3}+\frac {\tan ^{-1}\left (\sqrt {2} x\right )}{\sqrt {2}}\\ \end {align*}

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Mathematica [A]  time = 0.01, size = 25, normalized size = 1.00 \begin {gather*} \frac {x^3}{3}-x+\frac {\tan ^{-1}\left (\sqrt {2} x\right )}{\sqrt {2}} \end {gather*}

Antiderivative was successfully verified.

[In]

Integrate[(-x^2 + 2*x^4)/(1 + 2*x^2),x]

[Out]

-x + x^3/3 + ArcTan[Sqrt[2]*x]/Sqrt[2]

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IntegrateAlgebraic [F]  time = 0.00, size = 0, normalized size = 0.00 \begin {gather*} \int \frac {-x^2+2 x^4}{1+2 x^2} \, dx \end {gather*}

Verification is not applicable to the result.

[In]

IntegrateAlgebraic[(-x^2 + 2*x^4)/(1 + 2*x^2),x]

[Out]

IntegrateAlgebraic[(-x^2 + 2*x^4)/(1 + 2*x^2), x]

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fricas [A]  time = 0.74, size = 20, normalized size = 0.80 \begin {gather*} \frac {1}{3} \, x^{3} + \frac {1}{2} \, \sqrt {2} \arctan \left (\sqrt {2} x\right ) - x \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate((2*x^4-x^2)/(2*x^2+1),x, algorithm="fricas")

[Out]

1/3*x^3 + 1/2*sqrt(2)*arctan(sqrt(2)*x) - x

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giac [A]  time = 0.35, size = 20, normalized size = 0.80 \begin {gather*} \frac {1}{3} \, x^{3} + \frac {1}{2} \, \sqrt {2} \arctan \left (\sqrt {2} x\right ) - x \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate((2*x^4-x^2)/(2*x^2+1),x, algorithm="giac")

[Out]

1/3*x^3 + 1/2*sqrt(2)*arctan(sqrt(2)*x) - x

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maple [A]  time = 0.00, size = 21, normalized size = 0.84 \begin {gather*} \frac {x^{3}}{3}-x +\frac {\sqrt {2}\, \arctan \left (\sqrt {2}\, x \right )}{2} \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int((2*x^4-x^2)/(2*x^2+1),x)

[Out]

-x+1/3*x^3+1/2*arctan(x*2^(1/2))*2^(1/2)

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maxima [A]  time = 2.92, size = 20, normalized size = 0.80 \begin {gather*} \frac {1}{3} \, x^{3} + \frac {1}{2} \, \sqrt {2} \arctan \left (\sqrt {2} x\right ) - x \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate((2*x^4-x^2)/(2*x^2+1),x, algorithm="maxima")

[Out]

1/3*x^3 + 1/2*sqrt(2)*arctan(sqrt(2)*x) - x

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mupad [B]  time = 0.04, size = 20, normalized size = 0.80 \begin {gather*} \frac {\sqrt {2}\,\mathrm {atan}\left (\sqrt {2}\,x\right )}{2}-x+\frac {x^3}{3} \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

int(-(x^2 - 2*x^4)/(2*x^2 + 1),x)

[Out]

(2^(1/2)*atan(2^(1/2)*x))/2 - x + x^3/3

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sympy [A]  time = 0.14, size = 20, normalized size = 0.80 \begin {gather*} \frac {x^{3}}{3} - x + \frac {\sqrt {2} \operatorname {atan}{\left (\sqrt {2} x \right )}}{2} \end {gather*}

Verification of antiderivative is not currently implemented for this CAS.

[In]

integrate((2*x**4-x**2)/(2*x**2+1),x)

[Out]

x**3/3 - x + sqrt(2)*atan(sqrt(2)*x)/2

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