- A$-\frac{4\text{x}}{(\text{x}^2-1)^2}$
- B$-\frac{4\text{x}}{\text{x}^2-1}$
- C$\frac{1-\text{x}^2}{\text{4x}}$
- D$\frac{4\text{x}}{\text{x}^2-1}$
Solution:
$\text{y}=\frac{1+\frac{1}{\text{x}^2}}{1-\frac{1}{\text{x}^2}}$
$=\frac{\text{x}^2+1}{\text{x}^2-1}$
Differentiate both the sides with respect to x, we get
$\frac{\text{dy}}{\text{dx}}=\frac{(\text{x}^2-1)\frac{\text{d}}{\text{dx}}(\text{x}^2+1)-(\text{x}^2+1)\frac{\text{d}}{\text{dx}}(\text{x}^2-1)}{(\text{x}^2-1)^2}$ (Quotient rule)
$=\frac{(\text{x}^2-1)(\text{2x}+0)-(\text{x}^2+1)(\text{2x}-0)}{(\text{x}^2-1)^2}$
$=\frac{\text{2x}^3-\text{2x}-\text{2x}^3-\text{2x}}{(\text{x}^2-1)^2}$
$=\frac{-\text{4x}}{(\text{x}^2-1)^2}$
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
If slope of a line is 4 and y-intercept made by the line is 2 then the equation of line will be:
$\lim\limits_{\text{x} \rightarrow0}\frac{\big(\sqrt{\text{x}}-1\big)\big(2\text{x}-3\big)}{2\text{x}^{2}+\text{x}-3}$ is:
$\frac{1}{10}$
$-\frac{1}{10}$
$1$
None of these.