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Find the Magnitude, in Radians and Degrees, of the Interior Angle of a Regular Octagon. - Mathematics

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Question

Find the magnitude, in radians and degrees, of the interior angle of a regular octagon.

Solution

\[\text{ Sum of the interior angles of the polygon }= \left( n - 2 \right)\pi\]
Number of sides in the octagon = 8 
\[ \therefore \text{ Sum of the interior angles of the octagon }= \left( 8 - 2 \right)\pi = 6\pi\]
\[\text{ Each angle of the octagon }= \frac{\text{Sum of the interior angles of the polygon }}{\text{ Number of sides }} = \frac{6\pi}{8} = \frac{3\pi}{4}\text{ rad }\]
\[\text{ Each angle of octagon }= \left( \frac{3\pi}{4} \times \frac{180}{\pi} \right)^\circ= 135^\circ\]

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Chapter 4: Measurement of Angles - Exercise 4.1 [Page 15]

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RD Sharma Mathematics [English] Class 11
Chapter 4 Measurement of Angles
Exercise 4.1 | Q 5.2 | Page 15

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