$\left(6-20\right)+350$

$\left(2y^7\right)\left(4x^3y^2\right)\left(-5x\right)$

$183,4\:-\:64,125$

$\sin\left(\frac{\pi}{8}\right)\cos\left(\frac{5\pi}{6}\right)-\cos\left(\frac{5\pi}{8}\right)\sin\left(\frac{\pi}{8}\right)$

$+2-4+5-6+7-3+5-6+7$

$\lim_{x\to0}\left(\frac{e^{3x}-1-3x}{1-cos\left(3x\right)}\right)$