$$3x^4-65x^3$$

$$28.\left(-\frac{x}{2}\right)^6$$

$$\frac{1}{4}\cdot8-5$$

$$\cos\left(y\right)\frac{dx}{dy}=x\sin\left(y\right)+\tan\left(y\right)$$

$$\left(45-m\right)^2$$

$$\left(+3\right)\left(+8\right)$$

$$\lim_{x\to\infty}\left(\frac{x}{1-x}\right)$$