$\lim_{x\to0}\left(\frac{sin\left(3x\right)^2}{x^2\cdot cos\left(5x^3\right)}\right)$

$\lim_{x\to2}\left(\frac{x^2+x-6}{x+2}\right)$

$0.4\cdot0.8$

$\frac{1296-x^4}{6-x}$

$4x^2-8x^4-4y^3$

$\left(8x^2+9\right).\left(8x^2+4\right)$

$\lim_{x\to0}\left(\frac{1}{sin\left(t\right)cos\left(t\right)}-\frac{1}{t}\right)$