$\left(v^3+6v^2-v\right)-\left(9v^3-7v^2+3v\right)$

$\cos^225-\sin^225$

$-16x^2-144$

$\frac{\left(2x+69\right)}{\left(x-8\right)\left(x+9\right)}$

$-28=14k$

$\frac{d^2}{dx^2}\left(2x^3+5x^2+2\right)$

$\frac{1}{1+sin\left(x\right)}+\frac{1}{1-\sin\left(x\right)}=2\sec^2\left(x\right)$