题目内容
已知a,b满足等式(a+
)2+|3b+2|=0,求代数式
(a-b)+
(a+b)-
(a-b)+
(a+b)-
(a-b)的值.
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考点:整式的加减—化简求值,非负数的性质:绝对值
专题:计算题
分析:首先根据非负数的性质求出a和b,在根据乘法分配律化简代数式,然后代入求值.
解答:解:∵(a+
)2+|3b+2|=0,
∴a+
=0,3b+2=0,
∴a=-
,b=-
,
(a-b)+
(a+b)-
(a-b)+
(a+b)-
(a-b)
=
a-
b+
a+
b-
a+
b+
a+
b-
a+
b
=(
+
-
+
-
)a+(-
+
+
+
+
)b
=
a+
b
=
×(-
)+
×(-
)
=-
.
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| 3 |
∴a+
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| 3 |
∴a=-
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=
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=(
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=
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=
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=-
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点评:此题考查的知识点是整式的加减化简求值,关键是先根据非负性求出a、b的值.
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