just show this limit does not exists if
use the same formula above, but now, can be anything but zero. just leave it as and find the answerif a (can not = 0), find g'(a)
or simply use the power rule to differentiate and plug in
hint: we have a vertical tangent line if the slope is infinite.show that y = x^(2/3) has a vertical tangent line at (0,0)
how does the derivative relate to the slope?