Please help me solve the equation as shown as below.
Q. log(base4) (x+3) + log(base4) (x-3) = 2
Maths - logarithmic equations
2009-04-19 4:46 am
回答 (2)
2009-04-19 6:44 am
✔ 最佳答案
log4 (x+3) + log4(x-3) = 2 log4[(x+3)(x-3)]=2
(x+3)(x-3)=42
x2-9=16
x2=25
x=5或x=-5(rejected.)
2009-04-19 4:55 am
2 = log(base4)16, so the equation becomes
log(x +3) + log(x -3) = log16
(x+3)(x-3) = 16
x^2 - 9 = 16
x^2 = 25
x = 5.
log(x +3) + log(x -3) = log16
(x+3)(x-3) = 16
x^2 - 9 = 16
x^2 = 25
x = 5.
收錄日期: 2021-04-23 20:40:05
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090418000051KK02034