SOLUTION: What is the solution set of 5^x-1=e^x+1? What is the solution set of ln(x)=12/ln(x)-4?

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Question 847431: What is the solution set of 5^x-1=e^x+1?
What is the solution set of ln(x)=12/ln(x)-4?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What is the solution set of 5^(x-1) = e^(x+1)?
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Take the natural log of both sides to get:
(x-1)ln(5) = x+1
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x(ln(5)-1) = 1+ln(5)
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x = (ln(5)+1)/(ln(5)-1)
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x = 4.2817...
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What is the solution set of ln(x)=12/ln(x)-4?
ln(x)[ln(x)-4] = 12
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(ln(x))^2 - 4ln(x) - 12 = 0
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Factor:
(ln(x)-6)(ln(x)+2) = 0
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ln(x) = 6 or ln(x) = -2
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x = e^6 or x = e^(-2)
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Cheers,
stan H.
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