$$\frac{\frac{\left(x^2-xy+y^2\right)}{x^3+y^3}}{\frac{1}{x+y}}$$

$$2y^23x$$

$$\frac{x^4-15x^2-10x+24}{x+2}$$

$$\frac{2x+9}{x-4}+\frac{4}{x^2-16}-2$$

$$\int\left(3-5x\right)cos4x\:dx$$

$$\frac{-40}{-40}$$