$\frac{dy}{dx}y-3x^2+x=0$

$3a^2b+6ab-5a^3b^2+8a^2bx$

$4x^2+10x-6$

$f\left(5\right)=\left(5t+2\right)^2$

$\lim_{x\to\frac{1}{3}}\left(\frac{1}{3x-1}-\frac{3}{ln\left(6x-1\right)}\right)$

$\left(x+6\right)\left(x^2-6x+36\right)$

$\lim_{x\to13}\left(\frac{x^2-169}{x-13}\right)$