Question

Let f(x) be signum function, $g\left(x\right)=cos(\frac{\pi }{2}-x)$ and $h\left(x\right)=\left(sinx\right)(1–x^2)$, then which of the following is/are periodic function(s).

• A. g(h(x))
• B. h(f(x))
• C. g(f(x))
• D. f(g(x))

Answer 1

Answer: (B), (D)

The correct options are
B h(f(x))
D f(g(x))

From the definition of f(x), h(f(x)) and g(f(x)) both are constant functions