$\lim_{x\to0}\left(2\right)x^2-4x+2$

$a^1^0-49b^1^2$

$2-\tan\left(x\right)=4$

$\lim_{t\to\frac{\pi}{4}}\left(1-tanx\right)sec2x$

$\frac{dy}{dt}=t^2\left(1+y\right);y\left(o\right)=3$

$\left(x-7\right)\left(x-9\right)$

$\lim_{n\to\infty}\left(\frac{2^n+4^n}{e^n}\right)$