Proving Increasing Function: f'(x)=f(x) for all x

kmeado07
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Homework Statement



Let f : R(real numbers) (arrow) (0,infinity) have the property that f ' (x) = f (x) for all x. Show that f is an increasing functions for all x.

Homework Equations





The Attempt at a Solution



I know that if f ' (x) > 0 , where all of x belongs to a,b (not bounded) then f is strictly increasing on [a,b].

So i need to show that f(x) > 0 maybe?

Any help/guidelines would be much appreciated.
 
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