$\frac{d^2x}{dy^2}=x^5+4x^3+2$

$\left(3-x\right)^4$

$x''\left(t\right)-4x'\left(t\right)+4x\left(t\right)=30t^2e^2t$

$\left(12y^2-9z^6\right)^2$

$\int\frac{1}{x+2\left(x^2+1\right)}dx$

$\frac{4x^2-121}{2x-11}$

$\lim_{x\to0}\left(\frac{\ln\left(x\right)^3}{x^2-1}\right)$