$5y+4=49$

$\int_{-1}^{1-x^{2}}x^{2}dx$

$\int\frac{1}{\left(x^4+64\right)}dx$

$\frac{1}{4}\cdot8+3$

$\frac{dx}{dt}-x=t$

$\tan\left(b\right)+\frac{\cos\left(b\right)}{1-\sin\left(b\right)}=\frac{\cos\left(b\right)}{1-\sin^2\left(b\right)}$

$\lim_{x\to1}\frac{3x^2-1}{\sqrt{x+3}}$