Let $f\in C^1[-\pi,\pi]$. Define , for $n\in N$ b_n=$\int_{-\pi}^\pi f(x)sinntdx$. Which of the following statement are true? a) $b_n\to 0$, as $n\to \infty$
b)$nb_n\to 0$, as $n\to \infty$ Please give me hint for option b) I tried substitution method, as it value of f(-π)=f(π) were given then I could able to done it easily. But how to think without that condition?
