Proving The Mean Value Theorem

Slide the endpoints "A" and "B" to change the interval and secant line.

Slide the "Lift" button over to the right to see the result of subtracting the secant line from the function.

Notice that g(A) = g(B) = 0, no matter what the end points are, so that the hypotheses for Rolle's Theorem is satisfied, and we can apply it to g(x).

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