$\frac{5x+7}{3}+\frac{7-2x}{7}<5$

$\frac{1}{x^2}dx+\frac{1}{y^2}dy=0$

$27x^2-5x-4$

$f'\left(v\right)\:=-4v^{-5}cosv$

$\log3\left(27^x\right)=3x$

$-18\cdot27$

$\frac{\sin\left(x\right)}{1+\cos\left(x\right)}+\frac{1+\cos\left(x\right)}{\sin\left(x\right)}=2\cos\sec a$