Functions Question 229

Question: The value of $ \underset{x\to 2}{\mathop{\lim }},\frac{{3^{x/2}}-3}{3^{x}-9} $ is

[MP PET 2000]

Options:

A) 0

B) 1/3

C) $ 1/6 $

D) $ \ln 3 $

Show Answer

Answer:

Correct Answer: C

Solution:

$ \underset{x\to 2}{\mathop{\lim }}( \frac{{3^{x/2}}-3}{3^{x}-9} ) $ $ =\underset{x\to 2}{\mathop{lim}},( \frac{{3^{x/2}}-3}{{{({3^{x/2}})}^{2}}-3^{2}} ) $ $ =\underset{x\to 2}{\mathop{lim}}\frac{1}{{3^{x/2}}+3}=\frac{1}{6} $ .