Limits Continuity And Differentiability Question 93
Question: Which one of the following functions is differentiable for all real values of x?
Options:
A) $ \frac{x}{| x |} $
B) $ x| x | $
C) $ \frac{1}{| x |} $
D) $ \frac{1}{x} $
Show Answer
Answer:
Correct Answer: B
Solution:
Since $ \frac{x}{| x |} $ is not continuous function
$ \therefore $ it is not differentiable also. Also, L.H.D. and R.H.D. at $ x=0 $ not equal.
Thus, only function given in option ?b? gives differentiability for all real values of x.
BETA
