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JEE MainMathematicsModerateDefinite Integration

For any integer n, the integral
∫0π\mspace2muesin⁡2xcos⁡3\int_{0}^{\pi}\mspace{2mu} e^{\sin^{2}x}\cos^{3}(2n + 1)x dx has the
value.

Show answer and solution
∵f(x)=esin⁡2xcos⁡3(2n+1)x\because f(x) = e^{\sin^{2}x}\cos^{3}(2n + 1)x
f(π−x)=−esin⁡2xcos⁡3(2n+1)x=−f(x)f(\pi - x) = - e^{\sin^{2}x}\cos^{3}(2n + 1)x = - f(x)
Use property
∫02a\mspace2muf(x)dx=0\int_{0}^{2a}\mspace{2mu} f(x)dx = 0 (where f(2a - x) =
- f(x))

Source: Grass-G / M-13 Mathematics Paper 4 Nov.docx

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