$$\frac{-6x-31x+30}{x-4}$$

$$\int4x^3e^{-2x}dx$$

$$\left(5x^2-2y^3\right)^3$$

$$\lim_{x\to a}\left(\frac{\left(a^2-ax\right)}{a-\sqrt{ax}}\right)$$

$$\frac{\sqrt{x^2-8x+16}}{\left(x-4\right)\left(e^{2x}\right)}$$

$$\int d^3$$

$$\frac{\cos\left(x\right)+\cos\left(x\right)\cot\left(x\right)}{\sin\left(x\right)+\cos\left(x\right)}$$