8 views

A function is given by $f(t)=\sin ^{2} t+\cos 2 t$. Which of the following is true?

1. $f$ has frequency components at 0 and $1 / 2 \pi \; \mathrm{Hz}$
2. $f$ has frequency components at 0 and $1 / \pi \; \mathrm{Hz}$
3. $f$ has frequency components at $1 / 2 \pi$ and $1 / \pi \; \mathrm{Hz}$
4. $f$ has frequency components at $0,1 / 2 \pi$ and $1 / \pi \; \mathrm{Hz}$