问题
解答题
计算下列各式的值: (1)lg4+lg25-lne2+20×2-2; (2)已知a
|
答案
(1)lg4+lg25-lne2+20×2-2
=2lg2+2lg5-2+
1 |
4 |
=2-2+
1 |
4 |
=
1 |
4 |
(2)因为a
1 |
2 |
1 |
2 |
1 |
2 |
1 |
2 |
a
3 |
2 |
3 |
2 |
1 |
2 |
1 |
2 |
所以
a1+a-1+2 | ||||
a
|
25 |
110 |
5 |
22 |
计算下列各式的值: (1)lg4+lg25-lne2+20×2-2; (2)已知a
|
(1)lg4+lg25-lne2+20×2-2
=2lg2+2lg5-2+
1 |
4 |
=2-2+
1 |
4 |
=
1 |
4 |
(2)因为a
1 |
2 |
1 |
2 |
1 |
2 |
1 |
2 |
a
3 |
2 |
3 |
2 |
1 |
2 |
1 |
2 |
所以
a1+a-1+2 | ||||
a
|
25 |
110 |
5 |
22 |