Question

Coefficients of x11 in the expansion of (2x2 + x – 3)6 is

Solution

Correct option is

192

    (x – 1)6 (2x + 3)6

   (x6 – 6x5 + 15x4 – 20x3….).{(2x)6 + 6.(2x)5. 3 + 15(2x)4. 32 +…}

Coefficient of x11 is

18.25 – 6.26 = 25(18 – 12) = 192.

SIMILAR QUESTIONS

Q1

In the binomial expansion of (a – b)n, n ≤ 5, the sum of the 5th and 5thterms is zero. Then  equals

Q2

The coefficient of x8 in the expression of 

Q3

The coefficient of xn in the expansion of (1 + x) (1 – x)n is

Q5

Sum of coefficient in the expansion of (x + 2y + z)10 is

Q6

If the sum of the coefficients in the expansion of (1 – 3x + 10x2)n is A and it the sum of the coefficients in the expansion of (1 + x2)is 

B, then

Q7

The coefficient t24 in (1 + t2)12 (1 + t12) (1 + t24) is

Q8

For natural number mn if (1 – y)m (1 + y)n = 1 + ay + ay2 +….. and a1 = a2 = 10, them (mn) is

Q9

If x is + ive, the first – ive term in the expansion of (1 + x)27/5 is:

Q10

Coefficients of x10 in the expansion of (1 + x2 – x3)8 is