log
3
x=5 即 x=3
5
=243, 例 log
3
(10x+43)=5 即 10x+43=3
5
=243, x=20
log
2
(4x-6)+log
2
(5x+3)=4 乘 log
2
(4x-6)(5x+3)=4 即
20x
2
-18x-18=2
4
得 x=1.793 或 x=-0.893 (捨去)
QUESTION
1
2
3
4
5
6
7
無解入 none, 最多取三位小數
如有兩解, 先入大數 x=3或x=-2
YOUR ANSWER
correct answer
TIME:
