$69\left(-65\right)$

$\left(-5\right)\left(-4\right)\left(-7\right)\left(-4\right)$

$\int\frac{1}{\sin\left(3x\right)}dx$

$\int\frac{1}{\sqrt{a^2-\left(x+b\right)^2}}dx$

$2x^2-2x-8\:=\:-4$

$\int\frac{2x^3-x-8}{\left(x^2-x\right)\left(x^2+4\right)}dx$

$y'+y\tan\left(x\right)=\sin\left(2x\right)$