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(1)计算:(log25)2-4log25+4+log215(2)(log43+log83)(log32+log92).

题目详情
(1)计算:
( log 2 5) 2 -4 log 2 5+4
+lo g 2
1
5

(2)(log 4 3+log 8 3)(log 3 2+log 9 2).
▼优质解答
答案和解析
(1)原式=
(lo g 2 5-2 ) 2
-lo g 2 5 =log 2 5-2-log 2 5=-2.
(2)原式= (
lg3
2lg2
+
lg3
3lg2
)(
lg2
lg3
+
lg2
2lg3
) =
lg3
lg2
lg2
lg3
(
1
2
+
1
3
)(1+
1
2
) =
5
6
×
3
2
=
5
4