$$\frac{1}{2\left(\frac{2x-1}{2x+1}\right)-1}$$

$$-6-\left(+5-\left|6-\left(-2+5\right)-5\right|-8\right)-2$$

$$y+\tan\left(x\right)y=\cos^2\left(x\right)$$

$$\lim_{x\to\infty}\left(3x^3+2x^2\right)\cdot e^{-3x}$$

$$\frac{1+\sin\left(-x\right)}{1+\csc\left(-x\right)}=-\sin\left(x\right)$$

$$y'=2xe^y$$

$$2\sin\left(x\right)\cos\left(x\right)-2\sin\left(x\right)+\cos\left(x\right)=1$$