NDA2025MathematicsBinomial TheoremActual
Which one of the following is the greatest coefficient in the expansion of (1 + x)¹⁰⁰ ?
Options
- AThe coefficient of x¹⁰⁰
- BThe coefficient of x⁹⁹
- CThe coefficient of x⁵¹
- DThe coefficient of x⁵⁰
Correct answer
D. The coefficient of x⁵⁰
Step-by-step solution
The general term in the expansion of (1 + x)^ n is given by T_ r+1 = ^ n C_ r x^ r , where the coefficient of x^ r is ^ n C_ r . For an even integer n , the greatest binomial coefficient is the middle term, which is ^ n C_ n/2 . Given n = 100 , which is even, the greatest coefficient is ¹⁰⁰C_ 100/2 = ¹⁰⁰C₅₀ . This corresponds to the coefficient of x⁵⁰ . Answer: The coefficient of x⁵⁰