Functions Question 67
Question: If $ f(a)=2,\ f’(a)=1,\ g(a)=-1;\ g’(a)=2 $ , then $ \underset{x\to a}{\mathop{\lim }}\frac{g(x)f(a)-g(a)f(x)}{x-a}= $
[DCE 1999; Karnataka CET 1999; MP PET 1995; Pb. CET 2004]
Options:
A) 3
B) 5
C) 0
D) -3
Show Answer
Answer:
Correct Answer: B
Solution:
$ \underset{x\to a}{\mathop{\lim }}\frac{f(a)[g(x)-g(a)]-g(a)[f(x)-f(a)]}{[x-a]} $ $ =f(a){g}’(a)-g(a){f}’(a)=2\times 2-(-1)(1)=5. $
BETA
