1.

In the expansion of `(1+x)^n ,`7th and 8th termsare equal. Find the value of `(7//x+6)^2`.

Answer» Correct Answer - `n^(2)`
Since the `7^(th)` and `8^(th)` terms are equal , we have
`.^(n)C_(6)x^(6) =.^(n)C_(7)x^(7)`
or `x=(.^(n)C_(6))/(.^(n)C_(7))=(7)/(n-6)`
or `(7/x+6)=n^(2)`


Discussion

No Comment Found

Related InterviewSolutions