$4x-\frac{1}{5}x=\frac{19}{5}$

$\left(4x-4\right)\left(3x-1\right)$

$\int\frac{3x^2}{\sqrt{2+x^2}}dx$

$1x^2+9x-81$

$\lim\:_{x\to\:0}\left(xtan\left(\frac{12}{x}\right)\right)$

$\left(t-y\right)\left(t+y^2\right)$

$\tan\left(a\right)^2+\cot\left(a\right)^2=\sec\left(a\right)^2+\csc\left(a\right)^2-2$