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

$$\int\frac{1}{\left(x^{2}+6x+13\right)^{2}}dx$$

$$\left(3x^5y^6\right)\left(4x^3y^{-4}\right)$$

$$\int\frac{\left(sin\right)^3}{1-cosx}\:dx$$

$$t\frac{11}{t^2}$$

$$\int\left(-45\right)x^4e^{-9x^5+\left(-32\right)}dx$$

$$\lim_{x\to0}\left(\frac{\ln\left(1+x^2\right)}{x\cdot\sin\left(x\right)}\right)$$