$\lim_{x\to\infty}\left(\frac{x^3}{\sqrt{x^6+x^4-1}}\right)$

$\frac{3^4\cdot3^{-7}\cdot3^2}{2^{-12}\cdot2^8}$

$\left(2x+5bc+4y\right)^2$

$\frac{\sec\left(x\right)}{\csc\left(x\right)}=\tan^2\left(x\right)$

$\left(x^{a+1}-4x^{a.2}\right)^2$

$-9\cdot11$

$x^2y+2x^2-y-2=0$