$5x+y-4y+3x+y$

$\left(a^{x-1}-2b^{nx-1}\right)\left(2b^{x-1}+a^{x+1}\right)$

$\lim_{x\to\infty}\left(\frac{xcos\left(\frac{1}{x}\right)}{x+1}\right)$

$x\left(3x^2+4x-7\right)-2$

$\frac{d}{dx}\left(\frac{2}{3}x^{\frac{3}{2}}-\frac{1}{2}x^{\frac{1}{2}}\right)$

$4-\sin\left(x\right)=\frac{1}{\sin\left(x\right)}$