help with logarithms?

2008-12-13 7:39 am
Using suitable substitutions, solve this equation:
2e^x=3-e^(x+1)
更新1:

thanks a lot, but i'll give the best answer to whoever's answer actually HAS a substitution in it.

回答 (4)

2008-12-13 7:48 am
✔ 最佳答案
you have 2 e^x = 3 - e*e^x---> [2+e] e^x = 3---> x = ln[3/(2+e)] = ln 3 - ln(2+e)
2008-12-13 3:51 pm
2e^x = 3 - e¹e^x

2(e^x) + ee^x = 3

(e^x) (2 + e) = 3

e^x = 3 / (2+e)

ln(e^x) = ln(3 / (2+e))

x = ln(3/ (2+e)) ≈ -0.4528
2008-12-13 6:46 pm
2e^x = 3 - e^(x + 1)
2e^x + e^(x + 1) = 3
e^x(2 + e^1) = 3
e^x(2 + e) = 3
e^x = 3/(e + 2)
x = ln[3/(e + 2)]
2008-12-13 3:52 pm
2e^x = 3 - e^(x+1)
2e^x + e^(x+1) = 3
e^x = 3/(2+e)
x = ln(3/(2+e))

Answer: x = ln(3/(2+e)) ... ≈ -0.45283


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