Verified answer

Ответ:

[tex](x - 1) {}^{3} - 9(x - 1) = (x - 1)(x - 4)(x + 2) \\ (x - 1)((x - 1) {}^{2} - 9) = (x - 1)(x {}^{2} - 2x - 8) \\ (x - 1)(x {}^{2} - 2x + 1 - 9) = (x - 1)(x {}^{2} - 2x - 8) \\ (x - 1)(x {}^{2} - 2x - 8) = (x - 1)(x {}^{2} - 2x - 8)[/tex]

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