Differentiation Question 183
Question: Let $ f(x)=4 $ and $ f’(x)=4. $ Then $ \underset{x\to 2}{\mathop{\lim }}\frac{xf(2)-2f(x)}{x-2} $ is given by
Options:
A) 2
B) -2
C) -4
D) 3
Show Answer
Answer:
Correct Answer: C
Solution:
[c] We have, $ \underset{x\to 2}{\mathop{\lim }}\frac{xf(2)-2f(x)}{x-2}( \frac{0}{0} ) $ By applying -L- Hospital rule, we get $ =\underset{x\to 2}{\mathop{\lim }}f(2)-2f’(x)=f(2)-2f’(2) $
$ =4-2\times 4=-4. $
BETA
