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问题: 初中化简

化简:{a+[(a+8)/3]*√[(a-1)/3]}*^(1/3)+{a-[(a+8)/3]*√[(a-1)/3]}*^(1/3)

解答:

解 设x=√[(a-1)/3],则a=3x^2+1,(a+8)/3=x^2+3.
原式={3x^2+1+(x^2+3)x}^(1/3)+{3x^2+1-(x^2+3)x}^(1/3)
={x^3+3x^2+3x+1}^(1/3)+{-x^3+3x^2-3x+1}^(1/3)
={(x+1)^3}^(1/3)+{(1-x)^3}^(1/3)
=x+1+1-x=2.