A)Let An be the area of a polygon with n equal sides inscribed in a circle with radius r. By dividing the polygon into n congruent triangles with central angle 2pi/n, show that An=(1/2)nr^2sin(2pi/n).(adsbygoogle = window.adsbygoogle || []).push({});

B)Show that the limit as n approaches infinity = pir^2.

Now, for part A, I don't understand how you can take the sin of the angle, because it is not a right triangle. And even if you divided the triangle in half, wouldn't it be more beneficial to take the tan, because then you would be getting the base and height of the triangle? I just need help on where to start this problem.

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# Areas and distances

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