问题 解答题
(1)当t=
1
8
时,计算
t+1
3t
+1
+
t-1
3t2
+
3t
+1
-
t-
3t
3t
-1

(2)计算
2lg2+lg3
1+
1
2
lg0.36+
1
3
lg8
答案

(1)∵t=

1
8

t+1
3t
+1
+
t-1
3t2
+
3t
+1
-
t-
3t
3t
-1

=

3t2
-
3t
+1+
3t
-1
-
t-
3t
3t
-1

=

3t2
-
t-
3t
3t
-1

=

3
1
64
-
1
8
-
3
1
8
3
1
8
-1

=

1
4
-
3
4
=-
1
2

(2)

2lg2+lg3
1+
1
2
lg0.36+
1
3
lg8

=

lg(4×3)
lg(10×0.6×2)

=

lg12
lg12
=1.

综合
单项选择题 A1型题