Inscribed and described circle

Find the radii of a circle inscribed and circumscribed by a regular pentagon whose side measures 3 cm.

Correct answer:

r =  2.0646 cm
R =  2.552 cm

Step-by-step explanation:

a=3 cm n=5 α=π/n=3.1416/50.6283 rad  r=2 tanαa=2 tan0.62833=2.0646 cm
R=2 sinαa=2 sin0.62833=2.552 cm



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planimetricsgoniometry and trigonometryUnits of physical quantitiesGrade of the word problem

 
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