Binomial TheoremHard
Question
In the binomial expansion of (a - b)n, n ≥ 5 the sum of the 5th and 6th terms is zero. Then, a / b equals
Options
A.

B.

C.

D.

Solution
Given, T5 + T6 = 0
⇒ nC4an-4b4 - nC5an-5b5 = 0
⇒ nC4an-4b4 = nC5an-5b5
⇒
⇒ nC4an-4b4 - nC5an-5b5 = 0
⇒ nC4an-4b4 = nC5an-5b5
⇒

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