Question

If the term independent of x in the expansion of  is 405, then kequals

Solution

Correct option is

3, – 3

         

For this to be independent of xr must be 2. So that

             

SIMILAR QUESTIONS

Q2
Q3

  

                                                                           

Q5

If A and B are coefficients of xn in the expansions of (1 + x)2n and (1 +x)2n–1 respectively, then A/B is equal to

Q6

The coefficient of xk in the expansion of E = 1 + (1 + x) + (1 + x)2 +…+ (1 + x)n is

Q7

Coefficient of x7 in the expansion of (1 – 2x + x3)6 is

Q8

Coefficient of x8 in the expansion of (1 + 2x – x3)6 is

Q9

If the middle tern in the expansion of  is 40 then x equals

Q10

In the third term in the expansion  is 2, then x equals