$\lim_{x\to0}\left(\frac{sin^2x}{2x^3}\right)$

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

$\left(1-\cot a^2\right)$

$\frac{4x^4-7x+2}{x^3-x}$

$\left(xyz+100\right)\left(xyz+100\right)$

$\left(x^3\cdot x^2\cdot x\right)\left(y\right)\left(5\cdot3\cdot2\right)$

$2x=5x+18$