$\left(5x-8\right)\left(5x-11\right)$

$\lim_{x\to4}\left(\frac{2x^2+3x+1}{x^2-2x-3}\right)$

$\frac{dy}{dx}=\frac{\sqrt{x}}{7y}$

$-9-12+5+12-\left(-9\right)$

$\left|2\left(-7\right)-1\right|-\left|5-\left(-7\right)\right|+\left(-7\right)^2$

$y^2-81y+1458$

$\sec\left(y\right)^2-\tan\left(y\right)\sec\left(y\right)=\frac{1}{1+\sin\left(y\right)}$