Posted by Haley on .
using f'(x) as the limit of h approaches 0 [f(x+h)f(x)]/h
find: f'(x), given f(x)=x

calculus 
Reiny,
the graph of f(x) = x
is a V with the vertex at the origin.
(made up of y = x in quadrant I and y = x in quadrant II)
your two graphs are y = x and y = x
I will do the second part as x > 0 for y = x
= lim ((x+h)  (x))/h as x > 0
= lim (x  h + x)/h as x> 0
= lim h/h
= 1
do the same with f(x) = y = x to show
a result of +1