$\left(20-b\right)^2$

$2\sin\left(3\right)=1$

$\lim_{x\to0}\frac{5x^2}{\sqrt{\left(1+x^2\right)}-\cos\left(3x\right)}$

$\lim_{x\to\infty}\left(ln3x-ln\left(x+8\right)\right)$

$\left(8-5\left(3\right)\right)+3$

$\int5^{6x}dx$

$\lim_{x\to\infty}\left(\frac{5x^2-3x}{e^x+2x}\right)$