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

$y=\frac{1}{1+\left(-\frac{1}{2e}\right)e^{-x}}$

$18\cdot4+18-\left(-2\right)+11$

$21+3x=-15$

$\frac{\sin\left(x\right)^2-\tan\left(x\right)}{\cos\left(x\right)^2-\cot\left(x\right)}$

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

$\frac{5}{11}x+\frac{2}{3}x-\frac{1}{6}x$