$$\int\frac{7}{x^2\sqrt{x^2-3}}dx$$

$$\int_0^4\left(1+2x^3\right)dx$$

$$\left(-4x+6y\right)^4$$

$$-a\:+\:7,1a\:+\:2a\:-\:3,5a$$

$$\left(x\:+\:1\right)\left(x\:-\:7\right)$$

$$100x^6-160x^3y^3+64y^6$$

$$\frac{15x^2}{10x}$$