12x^3-44x^2+49x=15求x,急,

hillsky20062022-10-04 11:39:541条回答

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55495415 共回答了21个问题 | 采纳率85.7%
原式=12x^3-44x^2+49x-15
=x(3x-5)(4x-8)+3(3x-5)
=(3x-5)(4x^2-8x+3)
=(3x-5)(2x-3)(2x-1)
=0
所以x=5/3或x=3/2或x=1/2
1年前

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