Coefficient of x11 in the expansion of (1+x2)4(1+x3)7(1+x4)12 is 1051 b. 1106 c. 1113 d. 1120
If the constant term in the binomial expansion of (x2−x1)n, n∈N is 15 then the value of n is equal to
Write down the binomial expansion of (1+x)n+1 , when x=8. Deduce that 9n+1−8n−9 is divisible by 64 where, n is a positive integer.
Consider a G.P. with first term (1+x)n, ∣x∣<1, common ratio 21+x and number of terms (n+1). Let ′S′ be sum of all the terms of the G.P., then
The coefficient of xn is ′S′ is