$\int \frac{1}{7+2 x^2} \cdot d x$
$\int \frac{1}{7+2 x^2} \cdot d x$
$\int \frac{1}{25-9 x^2} \cdot d x$
$\int \frac{1}{4 x^2-3} \cdot d x$
$\int \frac{1}{\cos x-\sqrt{3} \sin x} \cdot d x$
$\int \frac{1}{\cos x-\sin x} \cdot d x$
$\int \frac{1}{3-2 \cos 2 x} \cdot d x$
$\int \frac{1}{3+2 \sin x-\cos x} \cdot d x$
$\int \frac{1}{2+\cos x-\sin x} \cdot d x$
$\int \frac{1}{4-5 \cos x} \cdot d x$
$\frac{1}{x \cdot \log x \cdot \log (\log x)}$
$=\int \frac{1}{\log (\log x)} \cdot \frac{1}{x \cdot \log x} d x$
Put $\log (\log x)=t \quad \therefore \frac{1}{\log x} \cdot \frac{1}{x} d x=d t$
$\therefore \frac{1}{x \cdot \log x} d x=d t$
$\begin{aligned} \therefore I & =\int \frac{1}{t} d t=\log |t|+c \\ & =\log |\log (\log x)|+c .\end{aligned}$
$\frac{x^2}{\sqrt{9-x^6}}$
Put $x^3=t \quad \therefore 3 x^2 d x=d t \quad \therefore x^2 d x=\frac{1}{3} d t$
$\therefore I=\int \frac{1}{\sqrt{9-t^2}} \cdot \frac{d t}{3}$
$\begin{aligned} & =\frac{1}{3} \int \frac{d t}{\sqrt{3^2-t^2}} \\ = & \frac{1}{3} \sin ^{-1}\left(\frac{t}{3}\right)+c \\ = & \frac{1}{3} \sin ^{-1}\left(\frac{x^3}{3}\right)+c .\end{aligned}$
$\frac{\sqrt{\tan x}}{\sin x \cdot \cos x}$
Dividing numerator and denominator by $\cos ^2 x$, we get
$\begin{aligned} I & =\int \frac{\left(\frac{\sqrt{\tan x}}{\cos ^2 x}\right)}{\left(\frac{\sin x}{\cos x}\right)} d x \\ & =\int \frac{\sqrt{\tan x} \cdot \sec ^2 x}{\tan x} d x\end{aligned}$
$=\int \frac{\sec ^2 x}{\sqrt{\tan x}} d x$
Put $\tan x=t \quad \therefore \sec ^2 x d x=d t$
$\begin{aligned} \therefore I & =\int \frac{1}{\sqrt{t}} d t=\int t^{-\frac{1}{2}} d t \\ & =\frac{t^{\frac{1}{2}}}{1 / 2}+c=2 \sqrt{t}+c \\ & =2 \sqrt{\tan x}+c .\end{aligned}$
$\frac{1}{4 x+5 x^{-11}}$
$=\int \frac{x^{11}}{x^{11}\left(4 x+5 x^{-11}\right)} d x$
$=\int \frac{x^{11}}{4 x^{12}+5} d x$
$=\frac{1}{48} \int \frac{48 x^{11}}{4 x^{12}+5} d x$
$=\frac{1}{48} \int \frac{\frac{d}{d x}\left(4 x^{12}+5\right)}{4 x^{12}+5} d x$
$=\frac{1}{48} \log \left|4 x^{12}+5\right|+c \ldots\left[\because \int \frac{f^{\prime}(x)}{f(x)} d x=\log |f(x)|+c\right]$
$\frac{e^x \cdot \log \left(\sin e^x\right)}{\tan \left(e^x\right)}$
$=\int \log \left(\sin e^x\right) \cdot e^x \cot \left(e^x\right) d x$
Put $\log \left(\sin e^x\right)=t \quad \therefore \frac{1}{\sin \left(e^x\right)} \cdot \cos \left(e^x\right) \cdot e^x d x=d t$
$\therefore e^x \cdot \cot \left(e^x\right) d x=d t$
$\begin{aligned} \therefore I & =\int t d t=\frac{t^2}{2}+c \\ & =\frac{1}{2}\left[\log \left(\sin e^x\right)\right]^2+c .\end{aligned}$
$\frac{\left(x^2+2\right)}{\left(x^2+1\right)} \cdot a^{x+\tan ^{-1} x}$
$=\int a^{x+\tan ^{-1} x} \cdot\left(\frac{x^2+2}{x^2+1}\right) d x$
Put $x+\tan ^{-1} x=t$
$\begin{array}{c}\therefore\left(1+\frac{1}{1+x^2}\right) d x=d t \\ \therefore\left(\frac{1+x^2+1}{1+x^2}\right) d x=d t \\ \therefore\left(\frac{x^2+2}{x^2+1}\right) d x=d t \\ \therefore I=\int a^t d t=\frac{a^t}{\log a}+c \\ =\frac{a^{x+\tan ^{-1} x}}{\log a}+c .\end{array}$
$\tan 3 x \tan 2 x \tan x$
$\cos ^7 x$
$\tan ^5 x$
$\cos ^8 x \cdot \cot x$
$\frac{3 e^{2 x}+5}{4 e^{2 x}-5}$
$\frac{20+12 e^x}{3 e^x+4}$
$\frac{\cos x}{\sin (x-a)}$
$\frac{\cos 3 x-\cos 4 x}{\sin 3 x+\sin 4 x}$
$\int \sqrt{1+\sin 5 x} \cdot d x$
$\int \frac{x-2}{\sqrt{x+5}} \cdot d x$
$=\frac{2}{3}(x+5)^{\frac{3}{2}}-14 \sqrt{x+5}+c$.