L Hospital's Rule

Q. If f(x) has a derivative at x=a, then ${lim}_{x\to a}\frac{xf\left(a\right)-af\left(x\right)}{x-a}$ is equal to

1. $f\left(a\right)-a{f}^{\prime }\left(a\right)$
2. $af\left(a\right)-f^{\prime }\left(a\right)$
3. $f\left(a\right)+f^{\prime }\left(a\right)$
4. $af\left(a\right)+f^{\prime }\left(a\right)$

Q.

${lim}_{x\to \frac{\pi }{2}}(1-sinx)tanx$ will be equal to _____

1. 1

2. -1

3. 0

4. None of the above