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

$$\int\frac{x}{\left(1+x^4\right)arctan^3\left(x^2\right)}dx$$

$$\int\frac{\left(z^2+1\right)^2}{\sqrt{z}}dz$$

$$\int x^2ln\left(3x\right)\:dx$$

$$\lim_{x\to\infty}\left(\frac{\sqrt{7x^2+7x}}{3x+1}\right)$$

$$3\left(4y-2\right)$$

$$\frac{dy}{dx}+\left(2x-1\right)y=0$$