$\int\left(e^{-t}\cdot cos\left(-t\right)\right)dt$

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

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

$\left(x^9\right)x\left(y^9\right)$

$\int\:\left(\frac{x+1}{\left(x^2+2x+3\right)^7}\right)dx$

$16x^4-81y^6$

$\sin^{2}x+4\cos x+11$