Fourier Series — CSIR Net PYQ (Question 2)

A Fourier Series previous-year question (PYQ) from Mathematical Physics (CSIR Net). Read the question, check the correct answer, then practise the full topic.

Question 2 of 3 · 3.5 marks

Consider the periodic function $f\left(t\right)$ with time period $T$ as shown in the figure below
The spikes, located at $t=\frac{1}{2}(2n-1)$, where
$n=0,\pm 1,\pm 2,\cdots$, are Dirac-delta functions of strength $\pm 1$. The amplitudes $a_n$ in the Fourier expansion
$f(t)={\sum }_{n=-\infty }^{\infty }{a}_n{e}^{2\pi int/T}$
are given by

1. 1$(-1{)}^n$
2. 2$\frac{1}{n\pi }sin\frac{n\pi }{2}$
3. 3$isin\frac{n\pi }{2}$
4. 4$n\pi$

Correct answer: Option 3

About this question

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