$\int\left(4x^2+2x\right)\left(8x+2\right)dx$

$\frac{db}{dt}=\left(12-t\right)\left(t-21\right)$

$\frac{1}{\sin\left(x\right)}+\frac{1}{\tan\left(x\right)}=\cot\frac{x}{2}$

$x\frac{1}{5}=3$

$y'+\cos\left(x\right)y=\cos\left(x\right)\cdot e^{\sin\left(x\right)}$

$5.5x\:+\:4\:=\:8x\:-\:19$

$\frac{x}{2}=-6$