$\sec\left(2a\right)-\tan\left(2a\right)$

$\left(3b^2+2x\right)\left(3b^2+4x\right)$

$\frac{dy}{dx}-5y^2=-\frac{5}{2}x.y^3$

$\lim_{x\to3}\left(\frac{x^2-2x-3}{x^2+2x-3}\right)$

$csc\left(x\right)^2\cdot tan\left(x\right)\cdot\frac{1}{cos\left(x\right)}$

$\int_{-3}^0\left(5x+3\right)\left(x+3\right)^3\:dx$

$\lim_{x\to\frac{1}{2}}\left(\frac{4x^2-1}{2x^2-1}\right)$