I hope this is the right part of the forum for this question.

In the expansion of (1+ax)^4, the coefficient of x^3 is 1372. Find the constant a.

Please Help !! (Crying)

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- October 2nd 2009, 01:44 PMcreatively12Binomial Theorem or Binomial Coefficient
I hope this is the right part of the forum for this question.

In the expansion of (1+ax)^4, the coefficient of x^3 is 1372. Find the constant a.

Please Help !! (Crying) - October 2nd 2009, 01:54 PMDefunkt

So the coefficient of x^3 is

Can you solve this now? - October 2nd 2009, 01:55 PMgalactus
By the binomial expansion, .

Solve for a.

Understand the pattern. - October 2nd 2009, 02:06 PMcreatively12
Thanks, i got it now, i had to equate the 4C3 part of the expansion to 1372x^3

Thanks