Question

設凸k邊形的對角線的條數為f(k)，則凸k+1邊形的對角線的條數f(k+1)等于

1. A.
   f(k)+k-1
2. B.
   f(k)+k
3. C.
   f(k)+k+1
4. D.
   f(k)+k-2

Answer 1

A