4 如果y等于0,x=?
解:Y=0 即:3x^3-18x-12=0==>3x^2(x+2)-6(x+2)(x+1)=0==>
3(x+2)(x^2-2x-2)=0==>3(x+2)(x-1+根号3)(x-genhao 3-1)==>
x=-2,x=1+genhao3,x=1-genhao3
解:Y=0==>-X^3+3X-4=0==>X^3-3X+4=0==>(X+1)(X^2-4X+4)=0==>
(X+1)(X-2)^2=0==>X=-1,X=2。
解:Y=0 即:3x^3-18x-12=0==>3x^2(x+2)-6(x+2)(x+1)=0==>
3(x+2)(x^2-2x-2)=0==>3(x+2)(x-1+根号3)(x-genhao 3-1)==>
x=-2,x=1+genhao3,x=1-genhao3
解:Y=0==>-X^3+3X-4=0==>X^3-3X+4=0==>(X+1)(X^2-4X+4)=0==>
(X+1)(X-2)^2=0==>X=-1,X=2。
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