$6n+5<20$

$\frac{dy}{dx}\left(\frac{11}{x^{12}}\right)$

$\lim_{x\to0}\left(\left(1-5x\right)^{\frac{8}{x}}\right)$

$-4\left(x-y\right)-\left(2x+7y\right)$

$x^3+y^3-z^3+\left(x\cdot y+y\cdot z+z\cdot x\right)\cdot\left(x+y+z\right)-x\cdot y\cdot z$

$a^{-2}.a^{\frac{5}{3}}$

$\int\left(8cos^42t\right)dt$