question_answer

Suppose\[f(x)\]is differentiable at\[x=1\]and\[\underset{h\to 0}{\mathop{\lim }}\,\frac{1}{h}f(1+h)=5,\]then\[f'(1)\]equals     AIEEE  Solved  Paper-2005

A) 6             

B)        5             

C)                        4             

D)        3

Correct Answer: B

Solution :

Now,somust be finite asexist andcan be finite only, if \[f(1)=0\] and. So,