$1+\cos\left(a\right)^2+2\sin\left(a\right)^2$

$\sin\left(80\right)\cos\left(35\right)-\cos\left(80\right)\sin\left(35\right)$

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

$\lim_{x\to0}\left(\frac{\cos\left(x\right)-1+\frac{1}{2}x^2}{6x^4}\right)$

$\left(\frac{-4x^2}{5}\right)^2$

$\left(-8x-2y\right)^2$

$\frac{\left(3x^3-x+4\right)}{x^4+2x^3+x}$