$\left(x-3\right)\left(x-1\right)\cdot\frac{2x-3}{x-3}-\frac{x-2}{x-1}$

$100x^2-81x^2y^4$

$z^2-16z+256$

$\left(h+4\right)\left(h-3\right)$

$\frac{\left(sec^2\left(x\right)tan^2\left(x\right)\right)}{cot\left(x\right)csc^2\left(x\right)}$

$8^3-60^2+150^1-1125$