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> 有这样一道题“计算x2-2x+1x2-1÷x-1x2+x-x的值,其中x=2005”.甲同学把条件“x=2005”错抄成”x=2050“,但他的计算结果也是正确的,你说这是怎么回事?试一试,你就会有收
有这样一道题“计算x2-2x+1x2-1÷x-1x2+x-x的值,其中x=2005”.甲同学把条件“x=2005”错抄成”x=2050“,但他的计算结果也是正确的,你说这是怎么回事?试一试,你就会有收
题目简介
有这样一道题“计算x2-2x+1x2-1÷x-1x2+x-x的值,其中x=2005”.甲同学把条件“x=2005”错抄成”x=2050“,但他的计算结果也是正确的,你说这是怎么回事?试一试,你就会有收
题目详情
有这样一道题“计算
x
2
-2x+1
x
2
-1
÷
x-1
x
2
+x
-x
的值,其中x=2005”.甲同学把条件“x=2005”错抄成”x=2050“,但他的计算结果也是正确的,你说这是怎么回事?试一试,你就会有收获.
题型:解答题
难度:中档
来源:不详
答案
原式=
(x-1)
2
(x+1)(x-1)
×
x(x+1)
x-1
-x
=x-x
=0.
即原代数式的值与x的取值无关.
故甲同学把x的值抄错结果仍正确.
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题目简介
有这样一道题“计算x2-2x+1x2-1÷x-1x2+x-x的值,其中x=2005”.甲同学把条件“x=2005”错抄成”x=2050“,但他的计算结果也是正确的,你说这是怎么回事?试一试,你就会有收
题目详情
答案
=x-x
=0.
即原代数式的值与x的取值无关.
故甲同学把x的值抄错结果仍正确.