Letf :Â® Â be given by f ( x) = x2 - 4 . Then lim
x®-3
( x^2 - 4) = 5.
any help will be appraciated,thanks.
$\displaystyle \left|x^2-4-5\right|=\left|x-3\right|\left|x+3\right|$. Now if we only consider a neighborhood of radius $\displaystyle 1$ (i.e. $\displaystyle 0<|x+3|<1$ then we can say that $\displaystyle |x-3|<c$ for some $\displaystyle c$ (find it). Do you get the idea?