JEE Main & Advanced Mathematics Binomial Theorem and Mathematical Induction Question Bank Mock Test - Binomial Theorem

  • question_answer
    If the sum of the coefficients in the expansion of \[{{(a+b)}^{n}}\]is 4096, then the greatest coefficient in the expansion is

    A) 924      

    B) 792

    C) 1594               

    D) none of these

    Correct Answer: A

    Solution :

    [a] We know that the sum of the coefficients in a binomial expansion is obtained by replacing each variable by unit in the given expression. Therefore, sum of the coefficients in \[{{(a+b)}^{n}}\]is given by \[{{(1+1)}^{n}}\] \[\therefore 4096={{2}^{n}}\]or \[{{2}^{n}}={{2}^{12}}\]or \[n=12\] Hence, n is even. So, the greatest coefficient is \[^{n}{{C}_{n/2,}}\]i.e., \[^{12}{{C}_{6}}=924\].


You need to login to perform this action.
You will be redirected in 3 sec spinner