Question

Which of the following statement(s) is/are true for the curve $f\left(x\right)=\cos 2x$

• A. Graph of $f\left(x\right)$ is symmetrical with respect to $y-$axis
• B. Range of $f\left(x\right)$ is $[-2,2]$
• C. Range of $f\left(x\right)$ is $[-1,1]$
• D. Period of $f\left(x\right)$ is $2\pi$

Answer 1

Answer: (A), (C)

Range of $f\left(x\right)$ is $[-1,1]$


It can be observed from the graph
$\left(i\right)f\left(x\right)$ is symmetrical w.r.t. $y-$axis.
$\left(ii\right)$ Range of $f\left(x\right)$ is $[-1,1]$
$\left(iii\right)$ Period of $f\left(x\right)$ is $\pi$