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

$16\cos^2\left(x\right)-9=0$

$m^4-81$

$\int\frac{2}{sen\left(x\right)+cos\left(x\right)}dx$

$-5xy\left(-6x-y\right)$

$5\left(8+x\right)+9$

$\frac{\sec\left(x\right)-\cos\left(x\right)}{\csc\left(x\right)-\sin\left(x\right)}$