@ @QSS@ @æa@paˆ@pþàbÉà@ @
[Pascal's Triangle]
n
.k = 0,1,…,n C(n,k)
C(0, 0) = 1
11
121
1331
14641
1 5 10 10 5 1
1 6 15 20 15 6 1
1 7 21 35 35 21 7 1
.
.C(5, 3) + C(5, 4) = 10 + 5 = 15 = C(6, 4) ,
[The Binomial Theorem]
x− 1 , x2 + 2y , 3x − y ,x +y ,
x2
: .
n (x + y)n