MCQ
$\lim _{x \rightarrow 1} \frac{1-x^{\frac{-2}{3}}}{1-x^{\frac{1}{3}}}$ is equal to
  • 2
  • B
    1
  • C
    $\frac{2}{3}$
  • D
    $\frac{1}{3}$

Answer

Correct option: A.
2
A)
$\lim _{x \rightarrow 1} \frac{1-x^{-\frac{2}{3}}}{1-x^{-\frac{1}{3}}}=\lim _{x \rightarrow 1} \frac{1^2-\left(x^{-\frac{1}{3}}\right)^2}{1-x^{\frac{1}{3}}}$
$=\lim _{x \rightarrow 1} \frac{\left(1+x^{-\frac{1}{3}}\right)\left(1-x^{-\frac{1}{3}}\right)}{1-x^{-\frac{1}{3}}}$
$=\lim _{x \rightarrow 1}\left(1+x^{-1 / 3}\right)=2$
Alternate method:
Apply L- Hospital's Rule.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free