Tính tổng S = 1 - 1 3 C n 1 + 1 5 C n 2 - 1 7 C n 3 + . . . + ( - 1 ) n 2 n + 1 C n n
A. S = 2 . 4 . 6 . . . . 2 n 3 . 5 . 7 . . . ( 2 n + 1 )
B. S = ( 2 n ) ! ( n + 1 ) !
C. S = ( - 1 ) n n ! ( n + 1 ) ! ( 2 n ) !
D. S = ( - 1 ) 2 n + 1 ( 2 n ) ! ( 2 n + 1 ) !