$\int_0^{\pi}3\cos^2\:x\:dx$

$\frac{4x}{x-5}+\sin\left(88\right)\frac{2}{5-x}$

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

$m^2n^2+10mn$

$7x+3y+4\left(-3x+4y\right)$

$\log_{10}\left(b\right)=1.8$

$\frac{x}{x^2+2x}$