For N-sided polygon,
sum of interior angles is (2n-4)*90 degrees
also Pi radians = 180 degrees
a) pentagon (n=5)
sum of interior angles = 540 deg
since its regular pentagon, each interior angle is same = 540/5 =108 degres = 1.884 radians
b) hexagon (n=6)
sum of interior angles = 720 deg
since its regular hexagon, each interior angle is same = 720/6 =120 degres = 2.093 radians
c) octagon (n=8)
sum of interior angles = 1080 deg
since its regular hexagon, each interior angle is same = 1080/8 =135 degres = 2.355 radians
d) polygon (n=15)
sum of interior angles = 2340 deg
since its regular hexagon, each interior angle is same = 2340/15 =156 degres = 2.721 radians
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Naga Ramesh

IIT Kgp - 2005 batch


						

							For N-sided polygon,sum of interior angles is (2n-4)*90 degreesalso Pi radians = 180 degreesa) pentagon (n=5)sum of interior angles = 540 degsince its regular pentagon, each interior angle is same = 540/5 =108 degres = 1.884 radiansb) hexagon (n=6)sum of interior angles = 720 degsince its regular hexagon, each interior angle is same = 720/6 =120 degres = 2.093 radiansc) octagon (n=8)sum of interior angles = 1080 degsince its regular hexagon, each interior angle is same = 1080/8 =135 degres = 2.355 radiansd) polygon (n=15)sum of interior angles = 2340 degsince its regular hexagon, each interior angle is same = 2340/15 =156 degres = 2.721 radians----Please feel free to post as many doubts on our disucssion forum as you can. If you find any question difficult to understand - post it here and we will get you the answer and detailed solution very quickly. We are all IITians and here to help you in your IIT JEE preparation. All the best.