Find a if the coefficient of x² and x³ in the expansion of (3+ax)9 a

1.	Find a if the coefficient of x² and x³ in the expansion of (3+ax)9 are equal
Answer» Here, 9C2 x 3^7 x a^2 = 9C3 x 3^6 x a^3And we get, a = 9/14.

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