MHT CET2017MathematicsContinuity and Differentiability
If f x = x f o r ≤ 0 0 f o r > 0 then f ( x ) at x = 0 is
Options
- AContinuous but not differentiable
- BNot continuous but differentiable
- CContinuous and differentiable
- DNot continuous and not differentiable
Correct answer
A. Continuous but not differentiable
Step-by-step solution
Continuity at x = 0 lim x → 0 - f x = lim x → 0 x = 0 lim x → 0 + f x = 0 f ( 0 ) = 0 ∴ c o n t i n u o u s a t x = 0 For differentiability f ' ( 0 + ) = 0 f ' ( 0 − ) = 1 ∴ Not differentiable Alternative Diagram: It has sharp edge at x = 0 ∴ not differentiable but continuous