Functions Question 202

Question: $ \underset{x\to 0}{\mathop{\lim }},\frac{xe^{x}-\log (1+x)}{x^{2}} $ equals

[RPET 1996]

Options:

A) $ \frac{2}{3} $

B) $ \frac{1}{3} $

C) $ \frac{1}{2} $

D) $ \frac{3}{2} $

Show Answer

Answer:

Correct Answer: D

Solution:

Let $ y=\underset{x\to 0}{\mathop{\lim }},\frac{x,e^{x}-\log ,(1+x)}{x^{2}} $ , $ ( \frac{0}{0},form ) $ Applying L-Hospital’s rule, $ y=\underset{x\to 0}{\mathop{\lim }},\frac{e^{x}+x,e^{x}-\frac{1}{1+x}}{2x} $ , $ ( \frac{0}{0},form ) $ $ y=\underset{x\to 0}{\mathop{\lim }},\frac{1}{2},[ e^{x}+e^{x}+x,e^{x}+\frac{1}{{{(1+x)}^{2}}} ] $ $ y=\underset{x\to 0}{\mathop{\lim }},\frac{1}{2},[1+1+0+1]=\frac{3}{2} $ .