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> 计算:(1)计算:2cos45°+(2-1)0-(12)-1(2)化简:(1a-1)÷a2-1a2+a.-数学
计算:(1)计算:2cos45°+(2-1)0-(12)-1(2)化简:(1a-1)÷a2-1a2+a.-数学
题目简介
计算:(1)计算:2cos45°+(2-1)0-(12)-1(2)化简:(1a-1)÷a2-1a2+a.-数学
题目详情
计算:
(1)计算:2cos45°+(
2
-1)
0
-(
1
2
)
-1
(2)化简:
(
1
a
-1)÷
a
2
-1
a
2
+a
.
题型:解答题
难度:中档
来源:不详
答案
(1)原式=2×
2
2
+1-2
=
2
+1-2
=
2
-1;
(2)原式=
class="stub"1-a
a
•
a(a+1)
(a+1)(a-1)
=-
class="stub"a-1
a
•
a(a+1)
(a+1)(a-1)
=-1.
上一篇 :
.I can hardly imagine so pre
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(a+ba-b)2•2a-2b3a+3b-a2a2-b
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题目简介
计算:(1)计算:2cos45°+(2-1)0-(12)-1(2)化简:(1a-1)÷a2-1a2+a.-数学
题目详情
(1)计算:2cos45°+(
(2)化简:(
答案
=
=
(2)原式=
=-
=-1.