$\cos\left(7x\right)\sin\left(9x\right)$

$\left(rs-12\right)\left(rs+7\right)$

$\int_0^x\left(5e^{-5x}\right)dx$

$4x^2\:-\:2x\:-\:12\:=\:0$

$\frac{-\sin\left(x\right)+\sin\left(x\right)\cos\left(x\right)}{\cos\left(x\right)}=0$

$\int\frac{3x^3+4x^2-5x+7}{x^2\left(5x-5\right)^2}dx$

$\left(\frac{2}{3}x^4+5\right)^2$