Solve the simultaneous equations:
e^y + 5 - 9x = 0
y - ln ( x + 4 ) = 2
Thanks
maths (e and ln)
2009-07-05 1:11 am
回答 (1)
2009-07-05 1:31 am
✔ 最佳答案
e^y + 5 - 9x = 0...(1)y - ln ( x + 4 ) = 2...(2)
From (1) e^y=9x-5=>y=ln(9x-5)
From (2) y=2+ln(x+4)
So ln(9x-5)=2+ln(x+4)
ln[(9x-5)/(x+4)]=2
(9x-5)/(x+4)=e^2
9x-5=(e^2)(x+4)
(9-e^2)x=5+4e^2
x=(5+4e^2)/(9-e^2)
y=ln(9x-5)=ln[(41e^2)/(9-e^2)]=ln41+2-ln(9-e^2)
收錄日期: 2021-04-26 13:44:40
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090704000051KK01236