F4. 對數函數 (2)

1.
log(x + 1) = 1
x + 1 = 10¹
x + 1 = 10
x = 9

2.
log(3x + 4) = 2
3x + 4 = 10²
3x + 4 = 100
3x = 96
x = 32

3.
log(2x - 5) = 0
2x - 5 = 10⁰
2x - 5 = 1
2x = 6
x = 3

4.
log(5x - 3) = -1
5x - 3 = 10⁻¹
5x - 3 = 0.1
5x = 3.1
x = 0.62

5.
log₂(x - 3) = 4
x - 3 = 2⁴
x - 3 = 16
x = 19

6.
log₃(x + 2) = 3
x + 2 = 3³
x + 2 = 27
x = 25

7.
log₆(3x + 2) = 0
3x + 2 = 6⁰
3x + 2 = 1
3x = -1
x = -1/3

8.
log₅(8x - 3) = -1
8x - 3 = 5⁻¹
8x - 3 = 0.2
8x = 3.2
x = 0.4

9.
log(x - 2) = log 13
x - 2 = 13
x = 15

知足常樂回答correct