answer this question,plz,thank

Q2題意不明!　　　　　　　　　　　　

2011-03-11 20:21:15 補充：
Formula: C(n, k)+C(n, k+1)=C(n+1, k+1)
1.
C(n, r)+C(n, r-1)+C(n+1, r-1)+...+C(n+k, r-1)
=C(n, n-r)+C(n, n-r+1) +C(n+1, n-r+2)+...+C(n+k, n-r+k+1)
=C(n+1, n-r+1) + C(n+1, n-r+2) +...+C(n+k, n-r+k+1)
=C(n+2, n-r+2) +...+C(n+k, n-r+k+1)
= ...
=C(n+k+1, n-r+k+1)
=C(n+k+1, r)

2.
[C(n,0)+C(n,1)]*[C(n,1)+C(n,2)]*...*[C(n, n-1)+C(n,n)]
=C(n+1,1)*C(n+1,2)*...*C(n+1,n)
=[(n+1)/1 ]*[(n+1)n /(1*2)]*[(n+1)n(n-1)/(1*2*3)]*...*[(n+1)n*(n-1)*...*2]/n!
=(n+1)^2 *C(n,1)/2!*[(n+1)n(n-1)/3!]*...*[(n+1)n(n-1)*..*2]/n!
=(n+1)^3 *C(n,1)*C(n,2)/3! *...*[(n+1)n(n-1)*...*2]/n!
=...
=(n+1)^n *C(n,1)C(n,2)*...*C(n, n-1) /n!
=(n+1)^n C(n,1)C(n,2)...C(n,n-1)C(n,n) /n! (note: C(n,n)=1)