Manipal MET2012MathematicsContinuity and Differentiability
If f(x)= array ll |x+2| ⁻¹(x+2) , & x -2 2 & x=-2 array . , then f(x) is
Options
- Acontinuous at x=-2
- Bnot continuous at x=-2
- Cdifferentiable at x=-2
- Dcontinuous but not derivable at x=-2 .
Correct answer
B. not continuous at x=-2
Step-by-step solution
f(x)= array cc |x+2| ⁻¹(x+2) , & x -2 2, & x=-2 array . array r _ x -2⁻ f(x)= _ h 0 f(-2-h) = _ h 0 |-2-h+2| ⁻¹(-2-h+2) array = _ h 0 -h ⁻¹ h =-1 and _ x -2⁺ f(x)= _ h 0 f(-2+h) aligned & = _ h 0 [ |-2+h+2| ⁻¹(-2+h+2) ] & = _ h 0 h ⁻¹ h =1 _ x -2⁻ f(x) & _ x -2⁺ f(x) aligned So, f(x) is not continuous as well as not differentiable at x=-2 .