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.