集合A={-4,x+3,x2-2x+2,x3+x2+3x+7}B={2,4,x3-2x2-x+7},A交B={2,5},求x的值

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集合A={-4,x+3,x2-2x+2,x3+x2+3x+7}B={2,4,x3-2x2-x+7},A交B={2,5},求x的值集合A={-4,x+3,x2-2x+2,x3+x2+3x+7}B={2,

集合A={-4,x+3,x2-2x+2,x3+x2+3x+7}B={2,4,x3-2x2-x+7},A交B={2,5},求x的值
集合A={-4,x+3,x2-2x+2,x3+x2+3x+7}
B={2,4,x3-2x2-x+7},A交B={2,5},求x的值

集合A={-4,x+3,x2-2x+2,x3+x2+3x+7}B={2,4,x3-2x2-x+7},A交B={2,5},求x的值
A交B={2,5},
则B中有x³-2x²-x+7=5
x³-2x²-x+2=0
x²(x-2)-(x-2)=0
(x+1)(x-1)(x-2)=0
x=1,x=-1,x=2
代入A
x=1,A={-4,4,1,12},没有2和5
x=-1,A={-4,2,5,4},这样A交B={2,5,4},不成立
x=2,A={-4,5,2,25},成立
所以x=2