$$\left(15+x\right)\left(15-x\right)$$

$$\sqrt{2x}+\sqrt{32x^5}$$

$$\lim_{x\to infinity}\left(10xtan\left(\frac{3}{x}\right)\right)$$

$$\frac{1}{1+\cos\left(x\right)}=\csc^2x-\csc x\cdot\cot x$$

$$2\cdot2\cdot2$$

$$15+\left|15\cdot4-3\cdot\left(7-3\right)\right|-9$$

$$\left(3w+2z\right)\left(9w^2-6wz+4z^2\right)$$