【初一下】【回答后给分】已知x²-2x=2,将代数式(x-1)²+(x+3)(x-3)+(x-3)(x-1)化简并求值.
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![【初一下】【回答后给分】已知x²-2x=2,将代数式(x-1)²+(x+3)(x-3)+(x-3)(x-1)化简并求值.](/uploads/image/z/2768677-61-7.jpg?t=%E3%80%90%E5%88%9D%E4%B8%80%E4%B8%8B%E3%80%91%E3%80%90%E5%9B%9E%E7%AD%94%E5%90%8E%E7%BB%99%E5%88%86%E3%80%91%E5%B7%B2%E7%9F%A5x%26%23178%3B-2x%3D2%2C%E5%B0%86%E4%BB%A3%E6%95%B0%E5%BC%8F%28x-1%29%26%23178%3B%2B%28x%2B3%29%28x-3%EF%BC%89%2B%EF%BC%88x-3%EF%BC%89%28x-1%29%E5%8C%96%E7%AE%80%E5%B9%B6%E6%B1%82%E5%80%BC.)
【初一下】【回答后给分】已知x²-2x=2,将代数式(x-1)²+(x+3)(x-3)+(x-3)(x-1)化简并求值.
【初一下】【回答后给分】已知x²-2x=2,将代数式(x-1)²+(x+3)(x-3)+(x-3)(x-1)化简并求值.
【初一下】【回答后给分】已知x²-2x=2,将代数式(x-1)²+(x+3)(x-3)+(x-3)(x-1)化简并求值.
(x-1)²+(x+3)(x-3)+(x-3)(x-1)
=(x-1)²+(x-3)[(x+3)+(x-1)]
=(x-1)²+(x-3)[2x+2]
=x²-2x+1+2x²+2x-6x-6
=2+1+2x²-4x-6
=3+2(x²-2)-6
=3+4-6
=1
原式化简=3x²-6x-5=3(x²-2x)-5,带入x²-2x=2,
得=1