问题
解答题
计算下列各题: (Ⅰ)(
(Ⅱ)lg22+lg5+lg5lg2. |
答案
(Ⅰ)原式=[(
)3]-3 2
+1 3
-(24)7 3
-13 4
=(
)-1+3 2
-23-17 3 =
+2 3
-8-17 3 =-6.
(Ⅱ)原式=lg2(lg2+lg5)+lg5
=lg2lg10+lg5 =lg2+lg5 =lg10 =1.
计算下列各题: (Ⅰ)(
(Ⅱ)lg22+lg5+lg5lg2. |
(Ⅰ)原式=[(
)3]-3 2
+1 3
-(24)7 3
-13 4
=(
)-1+3 2
-23-17 3 =
+2 3
-8-17 3 =-6.
(Ⅱ)原式=lg2(lg2+lg5)+lg5
=lg2lg10+lg5 =lg2+lg5 =lg10 =1.