I prove the key inequalities involving sin(x), x, and tan(x) that are necessary to compute the derivative of the sine function.
I show how Archimedes dealt with these inequalities in the context of comparing the circumference of a circle to the perimeters of inscribed and circumscribed polygons, with emphasis on the special role of convex curves. Then I give modern commentary on Archimedes' axioms. This lays the groundwork for determining the area constant of a circle and estimating pi.
This is Ep. 2 in a series of videos on the subtle and difficult parts of calculus that are usually not emphasized in a calculus class.
Ep. 1: • Derivative of sin(x), CAREFUL PROOF |...
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