Question
Evaluate the following:
$\int\frac{\text{dx}}{1+\cos\text{x}}$

Answer

Let $\int\frac{\text{dx}}{1+\cos\text{x}}$
$=\int\frac{\text{x}}{2\cos^2\frac{\text{x}}{2}}$ $\Big[\because\ 1+\cos\text{A}=2\cos^2\frac{\text{A}}{2}\Big]$
$=\frac{1}{2}\int\frac{1}{\cos^2\frac{\text{x}}{2}}\text{dx}$
$=\frac{1}{2}\int\sec^2\frac{\text{x}}{2}\text{dx}$
$=\frac{1}{2}\cdot\tan\frac{\text{x}}{2}\cdot2+\text{C}$ $\big[\int\sec^2\text{x dx}=\tan\text{x}\big]$
$=\tan\frac{\text{x}}{2}+\text{C}$

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

Represent the following families of curves by forming the corresponding differential equation:
$\text{y}^2=4\text{a}(\text{x}-\text{b})$
The items produced by a company contain 10% defective items. Show that the probability of getting 2 defective items in a sample of 8 items is $\frac{28\times9^6}{10^8}$.
Differentiate the function $sin ^{-1}({x\sqrt x})\ ,{0 \leq x \leq 1}$ w.r.t. to x.
Evaluate the following integrals:$\int\frac{\cos2\text{x}}{\sqrt{\sin^22\text{x}+8}}\text{ dx}$
Evaluate the following determinant:
$\begin{vmatrix}\text{a}+\text{ib}&\text{c}+\text{id}\\-\text{c}+\text{id}&\text{a}-\text{ib}\end{vmatrix}$
The following relation are defined on the set of real numbers.
aRb if $|\text{a}|\leq\text{b}$
Find whether these relation are reflexive, symmetric or transitive.
If a unit vector $\vec{\text{a}}$ makes an angle $\frac{\pi}{3}$ with $\hat{\text{i}},\frac{\pi}{4}$ with $\hat{\text{j}}$ and an acute angle $\theta$ with $\hat{\text{k}}$, and ,then find the value of $\theta$.
Let $\vec{\text{a}}=\hat{\text{i}}+\hat{\text{j}}+\hat{\text{k}},\vec{\text{b}}=\hat{\text{i}}$ and $\vec{\text{c}}=\text{c}_1\hat{\text{i}}+\text{c}_2\hat{\text{j}}+\text{c}_3\hat{\text{k}}.$ Then,
If $C_2 = -1$ and $C_3 = 1$, show that no value of $C_1$ can make $\vec{\text{a}},\vec{\text{b}}$ and $\vec{\text{c}}$ coplanar.
Prove the following: $\tan^{-1}\frac{1}{3} + \tan ^{-1}\frac{1}{5} + \tan ^{-1}\frac{1}{7} + \tan^{-1}\frac{1}{8}= \frac{\pi}{4}$
Write the plane $\vec{\text{r}}.(2\hat{\text{i}}+3\hat{\text{j}}-6\hat{\text{k}})=14$ in normal form.