$\left(x^2+3-2a\right)\left(x^2+3+2a\right)$

$\int\frac{x+2}{x^3-16x}dx$

$\sin\left(x-\pi\right)+\cos\left(2x\right)=0$

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

$\int_1^4\left(\frac{x}{x^2-4}\right)dx$

$x+\frac{1}{x}=\sqrt{5}$

$\int\left(\arcsec\left(\sqrt{x}\right)\right)dx$