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brb8705
Oct23-10, 05:29 PM
How would you write a proof that proves that the minimum area between a function and its tangent line is the tangent line evaluated at point p, where p is the midpoint on a given interval?

i.e. The minimum area between x^2, and its tangent line on the interval [0,1] is the tangent line evaluated at x=1/2

Thanks,

Office_Shredder
Oct23-10, 05:50 PM
I don't think that's true

HallsofIvy
Oct23-10, 09:47 PM
Which tangent line are you talking about? A function may have an infinite number of distinct tangent lines on an interval.

brb8705
Oct24-10, 10:18 AM
Right, out of all the tangent lines of a function on a interval which one is the minimum area between the function and a tangent line.

I'm looking for a proof to prove this:
The minimum area between x^2, and its tangent line on the interval [0,1] is the tangent line evaluated at x=1/2

Wizlem
Oct24-10, 11:52 AM
Just find the area as a function of p and then differentiatie and find where dA(p)/dp=0 where A is the area to find the extrema. Figure out if any is a minima and then also check endpoints of your range.