Rút gọn
S
k
=
C
n
0
−
C
n
1
+
C
n
2
−
C
n
3
+
.
..
+
−
1
k
C
n
k
,
0
≤
k
<
n
,
k
∈
N
,
n
∈
N
*
A.
S
k
=
1
−
C
n
k
B.
S
k
=
−
1
k
C
n
k
C.
S
k
...
Đọc tiếp
Rút gọn S k = C n 0 − C n 1 + C n 2 − C n 3 + . .. + − 1 k C n k , 0 ≤ k < n , k ∈ N , n ∈ N *
A. S k = 1 − C n k
B. S k = − 1 k C n k
C. S k = C n − 1 k − 1
D. S k = − 1 k C n − 1 k
