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> 先化简,再求值:(1x-2+1x+2)÷x2x2-4,其中x=2.-数学
先化简,再求值:(1x-2+1x+2)÷x2x2-4,其中x=2.-数学
题目简介
先化简,再求值:(1x-2+1x+2)÷x2x2-4,其中x=2.-数学
题目详情
先化简,再求值:
(
1
x-2
+
1
x+2
)÷
x
2
x
2
-4
,其中
x=
2
.
题型:解答题
难度:中档
来源:不详
答案
原式=(
class="stub"1
x-2
+
class="stub"1
x+2
)•
(x+2)(x-2)
x
2
=
class="stub"1
x-2
•
(x+2)(x-2)
x
2
+
class="stub"1
x+2
•
(x+2)(x-2)
x
2
=
class="stub"x+2
x
+
class="stub"x-2
x
=
class="stub"2x
x
=2.
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题目简介
先化简,再求值:(1x-2+1x+2)÷x2x2-4,其中x=2.-数学
题目详情
答案
=
=
=
=2.