因式分解的难题!已知X=2007,求(5-2X)^2+(2X+5)(5-2X)的值(b-a)^3-3(b-a)+2
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已知X=2007,求(5-2X)^2+(2X+5)(5-2X)的值

(5-2X)^2+(2X+5)(5-2X)

= (5-2X)*[(5-2X)+(5+2X)]

=(5-2X)*10

=(5-2*2007)*10

=(5-4014)*10

=-4009*10

=-40090

(b-a)^3-3(b-a)+2

(b-a)^3-3(b-a)+2

=(b-a)^3-1-3(b-a)+3

=(b-a-1)[(b-a)^2+(b-a)+1]-3(b-a-1)

=(b-a-1)[(b-a)^2+(b-a)+1-3]

=(b-a-1)[(b-a)^2+(b-a)-2]

=(b-a-1)(b-a+2)(b-a-1)

=(b-a-1)^2(b-a+2)