$sin\:y\:=\:2$

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

$\frac{7}{2}x^2+\frac{1}{3}x^2$

$\int\frac{\cos^2x}{1+\cos x}dx$

$\sec^2\left(28^o\right)-\tan^2\left(28^o\right)$

$\int\frac{e^{-x}}{e^{-x}-1}dx$

$\lim_{x\to0}\left(\frac{ln\left(x\right)}{x+1}\right)$