$\lim_{x\to0}\left(\frac{e^{2x}-1-2\cos\left(x\right)}{1-\sin\left(x\right)}\right)$

$4\left(3b+\left(-4\right)\right)-9$

$2\sin^2u-\sin u-1=0$

$cosx\left(1-sin^2x\right)^2$

$\frac{\frac{e^{2x}}{1+x^2}}{e^{2x}}$

$\frac{1}{2}\cdot7\left(6\right)$

$\left(3x+\frac{2}{5}\right)\left(3x-7\right)$