Question

The value of c for which Lagrange's theorem f(x) = |x| in the interval [-1, 1] is

• A. 1/2
• B. 1
• C. non-existent in the interval
• D. -1/2

Answer 1

The correct option is C

non-existent in the interval

f'(x) =1 at x > 0

and f'(x) = -1 at x < 0

So, it is not differentiable.