$\left(2a^4+3a^3-a^2+5a-1\right)\left(a-2\right)$

$\cos^2\left(y\right)-\sin^2\left(y\right)=1-2\sin\left(y\right)$

$\int_{3.3}^{11.6}\pi\left(.03\left(x-7.6\right)^2+3.5\right)^2dx$

$\cos\left(\left(90-a\right)-b\right)$

$\lim_{x\to0}\left(\frac{sin\left(3x\right)}{3x}\right)$

$-4\sqrt{80x}-5\sqrt{45x}$

$\lim_{x\to1}\left(\frac{5x^2+7x+2}{x+1}\right)$