JEE Main2003MathematicsProperties of TrianglesActual
The sum of the radii of inscribed and circumscribed circles for an n sided regular polygon of side a, is
Options
- Aa 4 ( 2 n )
- Ba ( n )
- Ca 2 ( 2 n )
- Dacot ( 2 n )
Correct answer
D. acot ( 2 n )
Step-by-step solution
( n )= a 2 r ; ( n )= a 2 R r+R= a 2 [ n + cosec n ] r+R= a 2 ( 2 n )