$\tan\left(x\right)=\frac{\frac{8}{17}}{\frac{15}{17}}$

$\left(8b^6-7\right)^2$

$x+x-y+8x+6y$

$\frac{sin^2\left(\frac{3\pi\:}{2}+\alpha\:\right)-\sin\:\left(\pi\:+\alpha\:\right)\cdot\:\sin\:\left(\alpha\:\right)}{\cos\:\left(\frac{\pi\:}{2}+\alpha\:\right)}$

$20x^2+20=-41x$

$\frac{2x^2-10x-3}{x^3+x^2-9x-9}$

$3\left(5n\:+\:3\right)\left(n\:-\:2\right)$