Question

The coefficient of x^p  and x^q  (p and q are positive integers) in the expansion of (1 + x)^{p + q}  are 

(A) equal 

(B) equal with opposite signs 

(C) reciprocal of each other 

(D) none of these

Answer 1

The correct option is (A) equal.

Coefficient of x^p and x^q in the expansion of (1 + x)^{p + q} are ^{p + q}C_p and ^{p + q}C_q

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