$\int_1^2\left(\frac{x}{x+y}\right)dy$

$\int\frac{1}{\sqrt{16-x^4}}-\frac{1}{4}dx$

$\lim_{x\to0}\left(\frac{arcsin\left(2x\right)}{arcsin\left(x\right)}\right)$

$18x^3+270x^2+10x+150$

$7x^2+21x<28$

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

$\frac{\left(3x^2+4x-8\right)}{x-2}$