Correct option (b),(c)
(A) It is given that f: R→R, g: R→R and h: R→R are differentiable functions.
Now, f(x) = x3 + 3x+ 2 Differentiating w.r.t. to x, we get
f '(x) = 3x2 + 2
g(f(x)) = x
Hence, option (A) is incorrect.
(B) For all x ∈ R :
Hence, option (B) is correct.
Hence, option (D) is incorrect