Question 981299: find d coefficient of x^6 in d expansion of (2-3x)^12
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! in the expansion of (a+b)^n
1 2 1 is (a+b)^2
1331 is (a+b)^3
14641 is (a+b)^4
That is 4C0 4C1 4C2 4C3 4C4
12C6 will contain x^6
This is 12C6 (2-3x)^6=
924 (2-3x)^6
it will be positive,because (-3)^6 is positive
That is 729
The coefficient is the product, or 673,596.
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