$\left(x^{2}-y\right)\cdot\left(-2\right)$

$\frac{2\left(x^2+1^2\right)}{4.x}$

$\left(-8\right)\cdot0,25$

$\frac{4x^3+2x^2-x+1}{2x^2-3x+2}$

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

$sec\left(-\frac{\pi}{18}\right)cos\frac{37\pi}{18}$

$\left(4x^2-7y^3\right)^5$