问题
解答题
(1)计算:
(2)(log43+log83)(log32+log92). |
答案
(1)原式=
-log25=log25-2-log25=-2.(log25-2)2
(2)原式=(
+lg3 2lg2
)(lg3 3lg2
+lg2 lg3
)=lg2 2lg3
•lg3 lg2
(lg2 lg3
+1 2
)(1+1 3
)=1 2
×5 6
=3 2
.5 4
(1)计算:
(2)(log43+log83)(log32+log92). |
(1)原式=
-log25=log25-2-log25=-2.(log25-2)2
(2)原式=(
+lg3 2lg2
)(lg3 3lg2
+lg2 lg3
)=lg2 2lg3
•lg3 lg2
(lg2 lg3
+1 2
)(1+1 3
)=1 2
×5 6
=3 2
.5 4