Question

If the coefficient of th. (r + 1) and (r + 2)th terms
in the expansion of (1 + x)14 are in A.P., then the
value of r is equal to
(1) 5 or 9
(2) 4 or 7
(3) 3 or 8
(4) 6 or 10​

Answer 1

Answer:

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