If the coefficient of 2nd 3rd and 4th terms in e expansion of (1 + x)n are in A.P., then the value of n is
(A) 2
(B) 7
(C) 11
(D) 14
Answers
Answer:
Explanation:
Coefficient of (r+1)th in the expansion of (1+x)
Coefficient of (r+1)th in the expansion of (1+x) n
Coefficient of (r+1)th in the expansion of (1+x) n is
Coefficient of (r+1)th in the expansion of (1+x) n is n
Coefficient of (r+1)th in the expansion of (1+x) n is n C
Coefficient of (r+1)th in the expansion of (1+x) n is n C r
Coefficient of (r+1)th in the expansion of (1+x) n is n C r
Coefficient of (r+1)th in the expansion of (1+x) n is n C r
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2.
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 =
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 +
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3 ⇒n(n−1)=n+
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3 ⇒n(n−1)=n+ 6
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3 ⇒n(n−1)=n+ 6n(n−1)(n−2)
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3 ⇒n(n−1)=n+ 6n(n−1)(n−2)
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3 ⇒n(n−1)=n+ 6n(n−1)(n−2)
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3 ⇒n(n−1)=n+ 6n(n−1)(n−2) ⇒6(n−1)=6+n
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3 ⇒n(n−1)=n+ 6n(n−1)(n−2) ⇒6(n−1)=6+n 2
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3 ⇒n(n−1)=n+ 6n(n−1)(n−2) ⇒6(n−1)=6+n 2 −3n+2
Coefficient of (r+1)th in the expansion of (1+x) n is n C r Given 2nd, 3rd and 4th terms are in A.P⇒2. n C 2 = n C 1 + n C 3 ⇒n(n−1)=n+ 6n(n−1)(n−2) ⇒6(n−1)=6+n 2 −3n+2⇒n
2
−9n+14=0⇒n=7