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Solve $$\int^{2}_{-2} \frac{x^2+x^6\sin{6x}}{x^2 +4} dx$$

What I did was $$\int^{2}_{-2} \frac{x^2+x^6\sin{6x}}{x^2 +4} dx$$

$$= \int^{2}_{-2} \frac{x^2}{x^2 +4} + \frac{x^6\sin{6x}}{x^2 +4} dx$$

$$= \int^{2}_{-2} 1- \frac{4}{x^2 +4} + \frac{x^6\sin{6x}}{x^2 +4} dx$$

$$=[x]^2_{-2}-[2\arctan{\frac{x}{2}}]^2_{-2} + \int^2_{-2}\frac{x^6\sin{6x}}{x^2 +4} dx$$

I am unable to solve for $$ \int^2_{-2}\frac{x^6\sin{6x}}{x^2 +4} dx$$

Steve
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    It is an odd function. Use https://math.stackexchange.com/questions/439851/evaluate-the-integral-int-frac-pi2-0-frac-sin3x-sin3x-cos3x/439856#439856 – lab bhattacharjee Nov 13 '18 at 12:49

1 Answers1

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$ \int^2_{-2}\frac{x^6\sin{6x}}{x^2 +4} dx$ is zero since $\frac{x^6\sin{6x}}{x^2 +4}$ is an odd function.

Mostafa Ayaz
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