$\lim_{x\to\infty}\left(\frac{6z^3+10z+5}{z^3+2z+1}\right)$

$\ln\left(3-4y\right)=x$

$\left(3\sqrt{a}-\left(4x^2\right)\right)\left(4x^2+3\sqrt{a}\right)$

$\left(4x^2-\frac{1}{3}\right)^2$

$\left(5+u\right)\left(u+3\right)$

$4x^2+12x+49$

$\left(12a^3b-6b^3c\right)^2$