MCQ
If $y = {\cot ^{ - 1}}({x^2})$, then ${{dy} \over {dx}}$ is equal to
- A${{2x} \over {1 + {x^4}}}$
- B${{2x} \over {\sqrt {1 + 4x} }}$
- ✓${{ - 2x} \over {1 + {x^4}}}$
- D${{ - 2x} \over {\sqrt {1 + {x^2}} }}$
$\frac{{dy}}{{dx}} = \frac{{ - 1}}{{1 + {{({x^2})}^2}}}\frac{d}{{dx}}({x^2}) $
$= \frac{{ - 1}}{{1 + {x^4}}}(2x) = \frac{{ - 2x}}{{1 + {x^4}}}$.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
$f(x)=\left\{\begin{array}{ccc}x^{5} \sin \left(\frac{1}{x}\right)+5 x^{2}& , & x<0 \\ 0 & , & x=0 \\ x^{5} \cos \left(\frac{1}{x}\right)+\lambda x^{2} & , & x>0\end{array} .\right.$
The value of $\lambda$ for which $f^{\prime \prime}(0)$ exists, is