Question
Question: The number of diagonals of a polygon of m sides is –...
The number of diagonals of a polygon of m sides is –
A
2!m(m−1)
B
2!m(m−2)
C
2!m(m−3)
D
2!m(m−5)
Answer
2!m(m−3)
Explanation
Solution
No. of sides = m, no. of vertices = m
No. of lines = mC2, No. of diagonals = mC2 – m
= 2m(m−1) – m = 2m(m−3)