$$9d+9d+9$$

$$\left(\frac{3}{8}a^3b+\frac{3}{5}x^2\right)\cdot\left(\frac{5}{3}x^2y^2+\frac{8}{3}a^3b^2\right)$$

$$\frac{\sqrt[7]{ab^3c^5}}{a^2bc}$$

$$\:4\left(3d+7f\right)-5f-3\left(9f+3d\right)$$

$$\int7-\frac{5}{3}x\:dx$$

$$5a\:\left(x+3\right)\:$$

$$x^4-2x^3+x^3$$