$\lim_{x\to\infty}\left(x^3\left(\frac{7}{x}-sin\frac{7}{x}\right)\right)$

$y=\frac{-9}{\left(3x^2\right)^3}$

$-3x\left(x^2-4x+6\right)$

$\frac{54\left(3x-2\right)}{6\left(x-2\right)\left(3x-2\right)}$

$\left(\frac{81x^2y^{\frac{4}{3}}}{9x^8y^{\frac{3}{4}}}\right)^{\frac{3}{2}}$

$10^4\cdot10^{-32}$

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