$$\left(2-8xy\right)\cdot\left(2+8xy\right)$$

$$10x^2-13x-3$$

$$3^3\cdot\sqrt{4}-4^2$$

$$\int7abt^4dt$$

$$\int_{-2}^2\left(\frac{16}{x^4}\right)dx$$

$$\left(-b\:2\:+\:7\right)\:\left(b\:2\:+\:7\right)\:$$

$$8x'+x^2=256$$