先化简,再求值.(1)x2-9x2+6x+9•3x3+9x2x2-3x,其中x= 发布时间:2017-05-25 04:38 │ 来源:www.tikuol.com 题型:解答题 问题: 先化简,再求值.(1)x2-9x2+6x+9•3x3+9x2x2-3x,其中x=-13.(2)2xx3+2x2+x÷x-1x2+x,其中x=-2.(3)4x2-12-4x÷4x2+4x+1x,其中x=-14.
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