$\frac{\frac{1+cosx}{sinx}}{\frac{sinx+sinxcosx}{cosx}}$

$\frac{a}{b}+\frac{3}{c}$

$\sin\left(x+\frac{\pi}{2}\right)+\sin\left(x\right)\tan\left(x\right)=\sec\left(x\right)$

$f\left(x\right)=-x^2+10x$

$\lim_{x\to\infty}\left(1+\frac{1}{2x}\right)^2$

$cos^2\left(x\right)\:+\:tan\left(x\right)=\frac{1}{cos^2\left(x\right)}-sin^2\left(x\right)$

$3n^4-n^3$