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Find the coefficient of x^6 in the expansion of (2x-3)^9
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The binomial expansion is this formula
= + + + + . . . + +
In our case, n = 9, a = 2x, b = -3. Therefore, the general term of the binomial expansion in our case is
, k = 0, 1, 2, 3, 4, 5, . . .
Then the term with x^6 is the fourth term of the expansion at k = 3
= = . ANSWER
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