$x\cdot y'+3y=\frac{1}{x}$

$3a^2bc^3\sqrt{ab}$

$-\frac{2\left(3x^2+1\right)}{x^2-1},\:t=0$

$x^2-5x+10<4$

$\frac{2n+3}{12^n\cdot\left(n^2+1\right)}$

$\left(\sin\left(1.1779\right)\right)^3\cdot\left(\cos\left(1.1779\right)\right)^4$

$\lim_{x\to\infty}\frac{\cos\left(x\right)}{\sin^2\left(0\right)}$