$\frac{\left(1-x\right)}{\left(x-1\right)}$

$8x^6-3x^6-2x^6$

$\int\frac{9x-5}{\left(x-1\right)\left(x+2\right)\left(x-3\right)}dx$

$7^2+6$

$\frac{\csc\left(t\right)-\sin\left(t\right)}{\csc\left(t\right)}$

$\left(x^5-5x^4-7x^3+53x^2-18x-72\right)$

$\int_2^{-2}-x\sqrt{4-x^2}dx$