Functions Question 148
Question: $ \underset{x\to a}{\mathop{\lim }},\frac{({x^{-1}}-{a^{-1}})}{x-a}= $
[MP PET 1994]
Options:
A) $ {x_{n+1}}=\sqrt{2+x_{n}},\ n\ge 1,\ $
B) $ \frac{-1}{a} $
C) $ \frac{1}{a^{2}} $
D) $ \frac{-1}{a^{2}} $
Show Answer
Answer:
Correct Answer: D
Solution:
$ \underset{x\to a}{\mathop{\lim }}\frac{(1/x)-(1/a)}{x-a}=\underset{x\to a}{\mathop{\lim }}\frac{a-x}{ax,(x-a)}=\underset{x\to a}{\mathop{\lim }}\frac{-1}{ax}=\frac{-1}{a^{2}} $ .
BETA
