Proving Integrability: f on [a,b] with c ∈ [a,b]

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Homework Statement


Prove if f is integrable on [a,b] then \exists c a\leq c \leq b so that \int_a^cf = \int_c^bf

The Attempt at a Solution


I know that you have to use the first fundamental theorem of calculus and start with:
g(x) = \int_a^xf(t)dt-\int_x^bf(t)dt

I'm not sure how to get started and to use this fact to help prove it. Any help would be really appreciated. Thanks!
 
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g(x) is a continuous function, right? Use the intermediate value theorem. What are g(a) and g(b)?
 
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