Question

The set of points at which f(x) = $\lim_{x \rightarrow 0}\frac{x\tan 2x - 2x\tan x}{\left( 1 - \cos 2x \right)^{2}}$ is differentiable –

• A. (– ∞, –1) ∪ (1, ∞)
• B. (– ∞, ∞)
• C. (0, ∞)
• D. (– ∞, 0) ∪ (0, ∞)

Answer 1

Answer: (B)

(– ∞, ∞)

Answer 2

differentiable at

∀ x ∈ R