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> (1)239x+6x4-2x1x(2)解方程:x2+4x-1=0-数学
(1)239x+6x4-2x1x(2)解方程:x2+4x-1=0-数学
题目简介
(1)239x+6x4-2x1x(2)解方程:x2+4x-1=0-数学
题目详情
(1)
2
3
9x
+6
x
4
-2x
1
x
(2)解方程:x
2
+4x-1=0
题型:解答题
难度:中档
来源:不详
答案
(1)原式=2
x
+3
x
-2
x
;
=3
x
;
(2)原方程可化为x2+4x=1,
方程两边同时加4得,x2+4x+4=1+4,
配方得:(x+2)2=5,
解得:x1=-2+
5
,x2=-2-
5
.
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题目简介
(1)239x+6x4-2x1x(2)解方程:x2+4x-1=0-数学
题目详情
(2)解方程:x2+4x-1=0
答案
=3
(2)原方程可化为x2+4x=1,
方程两边同时加4得,x2+4x+4=1+4,
配方得:(x+2)2=5,
解得:x1=-2+