$\left(\left(2a^2\right)^{-3}b^4\right)^{-3}$

$2^{\left(2^x\right)}+4^{\left(2^x\right)}=42$

$\left(12a-7b+4c\right)-\left(-13a-5b+4c\right)$

$x^2-2x-1=0$

$\lim_{x\to0}\left(\frac{\csc\left(2x\right)}{\csc\left(6x\right)}\right)$

$t\frac{dy}{dt}=\left(1+t\right)y$

$ydy=7xdx$