Question:
Let $f(x)$ be a differentiable function at $x=a$ with $f^{\prime}(a)=2$ and $f(a)=4$. Then lim $_{z \rightarrow a} \frac{x f(a)-a f(x)}{x-a}$ equals:
Correct Option: , 3
Solution:
By L-H rule
$L=\lim _{x \rightarrow a} \frac{f(a)-a f^{\prime}(x)}{1}$
$\therefore L=4-2 a$