given f(x)= 4e^x -1x + 4
a) find derivative
I got 4ex -1 (which is correct)
***b) find the equation of a tangent line:
I thought that to find the equation of the tangent line you go
[f(x) - f(x+h)] / h
so i did this, plugged in
[(4ex -1 ) - (4e(x+h) -1 )] / h
cancelled and retrieved -4e for my answer.
which is wrong..
help plzz