Question
$\text{If} \sin [\cot^{-1} ( x + 1)] = \cos(\tan^{-1}x), \text{then find x}.$

Answer

$\text{Writing} \cot^{-1} (\text{x + 1}) = \sin^{-1} \frac{1}{\sqrt{1 + ( \text{x + 1})^{2}}}$
$\text{and} \tan^{-1}\text{x} = \cos^{-1} \frac{1}{\sqrt{1 + \text{x}^{2}}}$
$\therefore \sin \bigg(\sin^{-1} \frac{1}{\sqrt{1+{\text{(x + 1)}}^{2}}}\bigg) = \cos \bigg(\cos^{-1} \frac{1}{\sqrt{1 + \text{x}^{2}}}\bigg)$
$1 + \text{x}^{2} + 2\text{x} + 1 = 1 + \text{x}^{2} \Rightarrow \text{x} = -\frac{1}{2}$

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

Similar questions

Can the mean of a binomial distribution be less than its variance?
Evaluate the following integrals:$\int\frac{\cos2\text{x}}{\sqrt{\sin^22\text{x}+8}}\text{ dx}$
Bag $I$ contains $3$ white and $4$ black balls, while Bag $II$ contains $5$ white and $3$ black balls. One ball is transferred at random from Bag $I$ to Bag $II$ and then a ball is drawn at random from Bag $II$. The ball so drawn is found to be white. Find the probability that the transferred ball is also white.
Find the point on the curve $y^2 = 8x$ for which the abscissa and ordinate change at the same rate.
Find $\frac{\text{dy}}{\text{dx}}$ of the functions given in Exercise:
$\text{y}^\text{x}=\text{x}^\text{y}$
A coin is biased so that the head is 3 times as likely to occur as tail. If the coin is tossed twice, find the probability distribution of number of tails.
If $\text{y}=\sqrt{\log\text{x}+\sqrt{\log\text{x}+\sqrt{\log\text{x}+\ .... \text{to }\infty}}},$ prove that $(2\text{y}-1)\frac{\text{dy}}{\text{dx}}=\frac{1}{\text{x}}$
If $|\vec{\text{a}}|=2,\big|\vec{\text{b}}\big|=5$ and $\big|\vec{\text{a}}\times\vec{\text{b}}\big|=8,$ find $\vec{\text{a}}.\vec{\text{b}}.$
Find the area of the parallelogram whose diagonals are:
$3\hat{\text{i}}+4\hat{\text{j}}$ and $\hat{\text{i}}+\hat{\text{j}}+\hat{\text{k}}$
Find $\big[\vec{\text{a}}\ \vec{\text{b}}\ \vec{\text{c}}\big]$, when
$\vec{\text{a}}=2\hat{\text{i}}-3\hat{\text{j}},\vec{\text{b}}=\hat{\text{i}}+\hat{\text{j}}-\hat{\text{k}}$ and $\vec{\text{c}}=3\hat{\text{i}}-\hat{\text{k}}$