AP EAMCET2011MathematicsContinuity and Differentiability
If f(x)=|x|+| x| for x (- 2 , 2 ) , then its left hand derivative at x=0 is
Options
- A0
- B-1
- C-2
- D-3
Correct answer
C. -2
Step-by-step solution
aligned & f(x)=|x|+| x| & LHD = _ h 0 f(0-h)-f(0) 0-h & = _ h 0 |0-h|+| (0-h)|-(0+0) 0-h & = _ h 0 h+ h -h =- _ h 0 (1+ h h ) & =-(1+1)=-2 aligned