$\int\frac{x-1}{x^2+5x+6}dx$

$\frac{12a^4}{8a^9}$

$tan\left(\frac{\pi\:}{4}-x\right)=\frac{\cos\:\left(x\right)-\sin\:\left(x\right)}{\cos\:\left(x\right)+\sin\:\left(x\right)}$

$2\sec^2x-\sec^4x$

$\frac{d^2}{dx^2}\left(16x^4-4x^2\right)$

$49u^2-28u+4$

$\int\:\left(\frac{3}{x+2}-\frac{4}{x+5}\right)dx$