$\frac{1\:-\:2.1\:z^{-1}}{\left(1\:+\:0.5\:z^{-1}\right)\left(1\:-\:0.8\:z^{-1}\right)}$

$\int\:\sin\left(3x-5\right)dx$

$8\sin^2\left(x\right)+3=7$

$\frac{1}{2}x-3>\frac{1}{2}x+1$

$\frac{6x^2yz}{w^2};\:x=-2;\:y=3;\:z=2;\:w=-1$

$\lim_{x\to0}\left(\frac{8sinx^2}{x}\right)$

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