$\frac{4-1}{\sqrt{1}-2}$

$\left(6x-9\right)\left(6x+11\right)$

$4xy-2y^2=0$

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

$\frac{tanx}{secx-1}-\frac{tanx}{secx+1}$

$\left(\frac{d}{2}-4\right)^2$

$\int_{-18}^{32}\left(\frac{1}{\sqrt{2x}}\right)dx$