Q22Multiple choice
If the coefficients of 2nd, 3rd and the 4th terms in the expansion of (1 + x)n are in A.P., then value of n is
- (A)2
- (B)7
- (c)11
- (D)14 n n n 2 [Hint: 2 C2 = C1 + C3 ⇒ n – 9n + 14 = 0 ⇒ n = 2 or 7] BINOMIAL THEOREM 145
If the coefficients of 2nd, 3rd and the 4th terms in the expansion of (1 + x)n are in A.P., then value of n is