Question
Evaluate: $\int \frac{x}{\sqrt{x+z} \sqrt{x+z}} d x$

Answer

Rationalize the given integrand we get
$ \Rightarrow \int \frac{x}{\sqrt{x+a}-\sqrt{x-b}} \times \frac{\sqrt{x+a}+\sqrt{x-b}}{\sqrt{x+a}+\sqrt{x-b}} dx$
$\Rightarrow \int \frac{x(\sqrt{x+a}-\sqrt{x-b})}{x+a-x-b} d x$
$\Rightarrow \int \frac{x(\sqrt{x+a}-\sqrt{x-b})}{a-b} d x$
$\Rightarrow \frac{1}{a-b} \int x(\sqrt{x+a}-\sqrt{x-b}) d x$
Assume $x =\sqrt{t}$
$\Rightarrow dx=\frac{dt}{2 \sqrt{t}}$
Substituting values of $t $, and $dt ,$
$\Rightarrow \int \sqrt{t} \frac{(\sqrt{\sqrt{t}+a}-\sqrt{\sqrt{t}-b)}}{2 \sqrt{t}(a-b)} d t$
$\Rightarrow \frac{1}{2(a-b)} \int(\sqrt{\sqrt{t}+a}-\sqrt{\sqrt{t}-b}) d t$
$\Rightarrow \frac{1}{2(a-b)} \int(\sqrt{t}+a)^{1 / 2} d t-\int(\sqrt{t}-b)^{1 / 2} d t$
$\Rightarrow \frac{1}{2(a-b)}\left(\frac{4}{3}\left(\sqrt{t}+a^2\right)^{\frac{3}{2}}-\frac{4}{3}\left(t-a^2\right)^{\frac{3}{2}}\right) $
$\text { now replacing } x =\sqrt{t}$
$\Rightarrow \frac{1}{2(a-b)}\left(\frac{2}{3}(x+a)^{\frac{3}{2}}-\frac{2}{3}(x-b)^{\frac{3}{2}}\right)$

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

$\int \text{(2x} - 3)^{5} + \sqrt{3\text{x + 2}}\text{ dx}$
If A and B are symmetric matrices, prove that AB – BA is a skew symmetric matrix.
Show that the vectores $\vec{\text{a}}=3\hat{\text{i}}-2\hat{\text{j}}+\hat{\text{k}},\vec{\text{b}}=\hat{\text{i}}-3\hat{\text{j}}+5\hat{\text{k}},\vec{\text{c}}=2\hat{\text{i}}+\hat{\text{j}}-4\hat{\text{k}}$from a right-angled triangle.
Show that the function defined by $g (x) = x – [x]$ is discontinuous at all integral points. Here $[x]$ denotes the greatest integer less than or equal to $x.$
If $y= P e^{a x}+ Q e^{b x}$ then show that$
\frac{d^2 y}{d x^2}-(a+b) \frac{d y}{d x}+a b y=0
$
If $\text{y}=\log\Big(\sqrt{\text{x}}+\frac{1}{\sqrt{\text{x}}}\Big),$ prove that $\frac{\text{dy}}{\text{dx}}=\frac{\text{x}-1}{2\text{x}(\text{x}+1)}$
Solve the following differential equations:
$\text{xy}\frac{\text{dy}}{\text{dx}}=1+\text{x + y + xy}$
In the following cases, determine whether the given planes are parallel or perpendicular, and in case they are neither, find the angles between them.
$2x - y + 3z - 1 = 0$ and $2x - y + 3z + 3 = 0$
Find the values of k so that the function f is continuous at the indicated point:
$\text{f(x)}\begin{cases}\frac{\text{k}\cos\text{x}}{\pi -2\text{x}}\ \text{if}\ \text{x}\neq \frac{\pi}{2}\\3, \ \ \ \ \ \ \ \ \text{if}\ \text{x} =\frac{\pi}{2}\end{cases}$
$\text{at} \text{x} = \frac{\pi}{2}$
Show that the relation $''\geq''$ on the set R of all real numbers is reflexive and transitive but not symmetric.