State Parseval's identity for Fourier sine series of a periodic funct…

Question

State Parseval's identity for Fourier sine series of a periodic function in $(0, l)$.

Also apply it to find the value of

$\frac{1}{1^4} + \frac{1}{3^4} + \frac{1}{5^4} + \frac{1}{7^4} + \dots$, where $f(x) = \begin{cases} x, & 0 < x \le \pi/2 \\ \pi - 2, & \pi/2 < x < \pi \end{cases}$

Related pages

• Parseval's Formula — topic
• Engineering Mathematics-II syllabus

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