Question
$\int\frac{1+\cos4\text{x}}{\cot\text{x}-\tan\text{x}}\text{dx}$

Answer

$\int\Big(\frac{1+\cos4\text{x}}{\cot\text{x}-\tan\text{x}}\Big)\text{dx}$
$=\int\frac{(1+\cos4\text{x})}{\big(\frac{\cos\text{x}}{\sin\text{x}}-\frac{\sin\text{x}}{\cos\text{x}}\big)}\text{dx}$
$=\int\frac{2\cos^22\text{x}\times\sin\text{x}\cos\text{x}}{(\cos^2\text{x}-\sin^2\text{x})}\text{dx}$
$=\int\frac{\cos^22\text{x}\times2\sin\text{x}\cos\text{x}}{\cos2\text{x}}\text{dx}$
$=\int\cos2\text{x}\sin2\text{x}\text{ dx}$
$=\frac{1}{2}\int2\sin2\text{x}\cos2\text{x dx}$
$=\frac{1}{2}\int\sin4\text{x dx}$
$=\frac{1}{2}\Big[-\frac{\cos4\text{x}}{4}\Big]+\text{c}$
$=-\frac{1}{8}\cos4\text{x}+\text{c}$

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

Find the direction cosines of the unit vector perpendicular to the plane $\vec{\text{r}}.\big(6\hat{\text{i}}-3\hat{\text{j}}-2\hat{\text{k}}\big)+1=0$ passing through the origin.
If $\text{A}=\begin{bmatrix}2&4&-1\\-1&0&2\end{bmatrix},\text{B}=\begin{bmatrix}3&4\\-1&2\\2&1\end{bmatrix},$ find $(AB)^T$
Find the points on the curve $y = x^3 $ at which the slope of the tangent is equal to the $y-$coordinate of the point.
If $\vec{\text{a}},\vec{\text{b}}$ are two vectors, then write the truth value of the following statement:$\big|\vec{\text{a}}\big|=\big|\vec{\text{b}}\big|\Rightarrow\vec{\text{a}}=\pm\vec{\text{b}}$
Using the definition, prove that the function $f : A \rightarrow B$ is invertible if and only if f is both one-one and onto.
Prove the following:
$2\tan^{-1}\frac{1}{2}+\tan^{-1}\frac{1}{7}=\tan^{-1}\frac{31}{17}$
Prove that the function $f$ given by $f(x) = x^3 - 3x^2 + 4x$ is strictly increasing on $R.$
Prove that the given vectors are coplanar:
$\hat{\text{i}}+\hat{\text{j}}+\hat{\text{k}},\ 2\hat{\text{i}}+3\hat{\text{j}}-\hat{\text{k}}$ and $-\hat{\text{i}}-2\hat{\text{j}}+2\hat{\text{k}}$
Find the vector and the cartesian equation of the line that passes through through (-1, 2, 7) and is perpendicular to the lines $\vec{r}=2 \hat{\imath}+\hat{\jmath}-3 \hat{ k }+\lambda(\hat{\imath}+2 \hat{\jmath}+5 \hat{ k })$ and $\vec{r}=3 \hat{\imath}+3 \hat{\jmath}-7 \hat{ k }+\mu(3 \hat{\imath}-2 \hat{\jmath}+5 \hat{ k })$.
Find a particular solution of the differential equation $\frac{d y}{d x}+2 y \tan x=\sin x$, given that $y =0$, when $x=\frac{\pi}{3}$.