先化简,再求(x-2)(x^2-2x+4)-x(x+3)(x-3)+(2x-1)^2的值,其中x=9/13

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先化简,再求(x-2)(x^2-2x+4)-x(x+3)(x-3)+(2x-1)^2的值,其中x=9/13

数学之美团为你解答
(x-2)(x^2-2x+4)-x(x+3)(x-3)+(2x-1)^2
= x³ - 2x²+4x - 2x²+4x - 8 - x³ +9x + 4x² - 4x +1
= 13x +1
= 13×9/13 +1
= 10