A.Maths f.4 Chapter 4 Binomial Theorem

1.Solve the equation n
n
C 2 =( n-1) (n+3/2), where n is a positive integar.
2.(a) Find the values of r in the following equations.
15 15
C r = C 2r
(b) 20 20
C 2r + 1 = C 2r+3

由於技術問題,所以個C其實係o係中間!
Thx!
更新: 1..個n 在C2上面
2a 兩個15在Cr同C 2r上面
2b 兩個20 在C 2r + 1 = C 2r+3上面
1 個解答 1