$x\cdot y'\:+y=x^4\cdot y^3$

$\lim_{x\to-2}\left(\frac{\sqrt[3]{3x^2-x-10}}{7x^2+13x-2}\right)$

$6x^2ym^2-4mx-6x^2-9xym^2b-6bm+9bx$

$\int\left(\frac{x-2}{x^2+x+1}\right)dx$

$\lim_{w\to7}\left(\frac{cos\left(wt\right)-cos\left(7t\right)}{49-w^2}\right)$

$-4\cdot x^4-y^4$

$10x+12\ge8x+8$