Question

The fundamental period of the function $f\left(x\right)=2cos\frac{1}{3}(x-\pi )$ is

• A. $6\pi$
• B. $4\pi$
• C. $2\pi$
• D. $\pi$

Answer 1

The correct option is A $6\pi$

$f\left(x\right)=2cos\left(\frac{x-\pi }{3}\right)=2cos(2\pi +\frac{x-\pi }{3})$
$\therefore$ Period of f (x) = $\frac{2\pi }{\frac{1}{3}}=6\pi$