Question

Let g(x) = f(x + l) + f(x – l) and

f(x) = $\left\{ \begin{matrix} k\left\{ 1–\frac{|x|}{\mathcal{l}} \right\}; & |x|\mathcal{\leq l} \\ 0; & |x| > \mathcal{l} \end{matrix} \right.\$ k > 1, l> 1then g(x) is

• A. Not differentiable at x = l/2
• B. Not differentiable at x = – l only
• C. Not differentiable at five points
• D. None of these

Answer 1

Answer: (C)

Not differentiable at five points

Answer 2

Drawing the curve

So not differentiable At x = ± 2l , ± l , 0