Please help with an integration problem...equation attached.

Question

anonymous · Answer

Prove that $$\int\limits_{0}^{1}x^2dx = 1/3 $$ by computing the \left endpoint approximation

freckles · Answer

so the other day we started from right endpoint

freckles · Answer

today we are going to start from left endpoint

anonymous · Answer

good memory, am I looking for an equation first?

freckles · Answer

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this is what f(x)=x^2 where x is between 0 and 1 looks like

we are going to build rectangles starting from the left endpoint
all rectangles with equal base
so we will still have the same deltax formula
that is we will divide  the length between the endpoints by n

we are coming up with the sum of the n rectangles expression 

then we are going to take n to go to infinity

freckles · Answer

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