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数学
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若实数x,y,z满足:
xy
x+2y
=1
、
yz
y+2z
=2
、
zx
z+2x
=3
,则x=______.
人气:434 ℃ 时间:2020-03-20 19:05:02
解答
由已知得
x+2y
xy
=1,即
2
x
+
1
y
=1①,
同理得
2
y
+
1
z
=
1
2
②,
2
z
+
1
x
=
1
3
③,
①+②+③得
1
x
+
1
y
+
1
z
=
11
18
④,
④-②得
1
x
-
1
y
=
1
9
,
与①相加得
3
x
=
10
9
解得x=
27
10
.
故答案为:
27
10
.
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