$\frac{\sec\left(a\right)}{\csc\left(a\right)}$

$9x^4+4x^2+8x+12-x^3-7x^2+5x$

$\lim_{x\to0}\left(\frac{\cot\left(3x\right)}{\cot\left(4x\right)}\right)$

$\int6x^2e^{-4x}dx$

$\left(p^2-17p+6\right)^2$

$\frac{d}{dx}x^3y-4xy^2=y+x^2$

$\lim_{x\to\infty}\left(ln\left(2x^2+1\right)-ln\left(x^2-1\right)\right)$