Question

The interval in which x must lie so that the greatest term in the expansion of $+ (T_{1} - T_{3} + T_{5} - ....)^{2}$has the greatest coefficient, is.

• A. $(x^{2} + a^{2})^{n}$
• B. $(x^{2} + a^{2})^{1/n}$
• C. $(x^{2} + a^{2})^{- 1/n}$
• D. None of these

Answer 1

Answer: (B)

$(x^{2} + a^{2})^{1/n}$

Answer 2

Here the greatest coefficient is $\frac{10!}{5!7!}$

$\frac{(2n)!}{n!}x^{2}$

And $\frac{(2n)!}{n!(n - 1)!}x^{n + 1}$

Hence the required interval is $\frac{(2n)!}{(n!)^{2}}x^{n}$.