$\sin^2a\tan a+\cos^2a\tan a+2\sin a\cos a$

$\frac{d^4}{dx^4}\left(x\cdot\cos\left(2x\right)\right)$

$2abc^3+2abc^2-50abc-50ab$

$x2\:-\:87x\:+\:1820\:=\:0$

$\int\sin\left(3x\right).e^{5x}dx$

$\lim_{x\to1}\left(\frac{x^{15}-1}{x^6-1}\right)$

$\int_1^4\frac{3x^2+x+32}{\left(x^2+16\right)\left(x+2\right)}dx$