What is the coefficient of $x^8$ in the expansion of $(x-1)^9$?

Using the binomial expansion we have (x - 1)⁹ = x⁹ - 9x⁸ + ....  and we don't need to go any further because we have the x⁸ term, for which we see that the coefficient is -9

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uh... -9...dang it