Question

Let $f$ and $g$ be periodic functions with the periods $T_{1}$ and $T_{2}$ respectively. Then $f+g$ is

• A. periodic with period $T_{1}+T_{2}$
• B. non-periodic
• C. periodic with the period $T_{1}$
• D. periodic when $T_{1}=T_{2}$

Answer 1

Answer: (D)

$f+g$ is a periodic function.