$a^2-10ab+25b^2$

$\left(\sqrt{x}-3y\right)\cdot\left(\sqrt{x}+3y\right)$

$\sqrt{a^3}\cdot\sqrt{b^4}+\sqrt{a^2}\cdot\sqrt{b^2}$

$\left(\frac{2}{3}a^2b^3-\frac{1}{5}b\right)\left(\frac{2}{3}a^2b^3+\frac{1}{5}b\right)$

$\int\frac{4}{x\left(x+2\right)}dx$

$\left(x^7y\frac{1}{2}-4a^4b\right)^4$

$tanx\left(1+cos^2x\right)=\frac{1}{\cos xsinx}$