$$\frac{\left(100x^2-y^2\right)}{\left(10x+y\right)}$$

$$7x+18^2-9y^2-5x$$

$$6\cos^2\left(x\right)-3=3-6\sin^2\left(x\right)$$

$$4-7\left(3x+2\right)$$

$$\left(2b^2-4b\right)^2$$

$$\left(2a-1\right)^3\left(2a-1\right)^3$$

$$\int\frac{x^2}{\sqrt[2]{25-x^2}}dx$$