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> 已知a-b=5,ab=-2,则1a-1b=______.-数学
已知a-b=5,ab=-2,则1a-1b=______.-数学
题目简介
已知a-b=5,ab=-2,则1a-1b=______.-数学
题目详情
已知a-b=5,ab=-2,则
1
a
-
1
b
=______.
题型:填空题
难度:中档
来源:不详
答案
∵a-b=5,ab=-2,
∴
class="stub"1
a
-
class="stub"1
b
=
class="stub"b-a
ab
=-
class="stub"a-b
ab
=-
class="stub"5
-2
=
class="stub"5
2
.
故答案为:
class="stub"5
2
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题目简介
已知a-b=5,ab=-2,则1a-1b=______.-数学
题目详情
答案
∴
故答案为: