$$\frac{-30x^2y^4-45x^2y^3z}{15x^2y^3}$$

$$4x^3-4$$

$$m^2+m+m^2+m+m^2+n$$

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

$$\left(13a^3-5b^2\right)\left(13a^3+5b^2\right)$$

$$2cos5xcos2x+2sin5xsin2x=-1$$

$$\lim_{x\to0}\left(1+8x\right)^{\frac{1}{4x}}$$