Find x :
3^(3x+2)+27^(x+1) =12
maths.Q
2007-07-27 10:42 pm
回答 (2)
2007-07-30 6:00 pm
✔ 最佳答案
3^(3x+2)+27^(x+1) =12 3^(3x+2)+3^[3(x+1)] =12 (27 = 3^3)
3^(3x+2) +3^(3x + 3) =12
3^(3x + 2) + 3 x 3^(3x + 2) = 12
3^(3x + 2) x (1 + 3) = 12 (3^(3x + 2) is the common factor)
3^(3x + 2) = 3
3x + 2 = 1
3x = -1
x = -1/3
2007-07-27 10:46 pm
3^(3x+2)+27^(x+1) =12
3^(3x+2)+3^3[^(x+1)] =12
3^(3x+2)+3^(3x+3)=12
3^(3x+2) x (1+3)=12
3^(3x+2) =12/4=3=3^1
3x+2=1
x=-1/3
3^(3x+2)+3^3[^(x+1)] =12
3^(3x+2)+3^(3x+3)=12
3^(3x+2) x (1+3)=12
3^(3x+2) =12/4=3=3^1
3x+2=1
x=-1/3
收錄日期: 2021-04-13 00:53:22
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070727000051KK02686