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I have to finish my summer homework and i am down to the last few and i just don't know how to finish them. And the reason i am doing it last minute is not because i am procrastinating. I have had a 9-6 job, at the Goddard School which is like a daycare/preschool, all summer to help pay for my car.

But the original math question is solve the equation:

ln x = ln (x+1) - 1 and i don't evem know where to start.

2007-08-26 05:31:43 · 11 answers · asked by webshell46 1 in Science & Mathematics Mathematics

11 answers

For all cases, no. But if you do want to find the solution as to when it is true, this is how you would go about it:

ln x = ln (x+1) - 1
e^(ln x) = e^(ln (x+1) - 1)
e^(ln x) = e^(ln (x+1))/e^1
x = (x+1)/e
ex = x+1
ex-x = 1
x(e-1) = 1
x = 1/(e-1)

2007-08-26 05:43:58 · answer #1 · answered by NSurveyor 4 · 2 0

I n x = I n (x+1) -1 = I n x

2007-08-26 12:54:10 · answer #2 · answered by V B 5 · 0 0

problem 1
As per logarithmic rules
ln(ab) = ln a + ln b --- product rule
ln(a/b) = ln - ln b ----- quotient rule
So ln(x+1) is not equal to ln(x) + ln(1)
because ln(x) + ln(1) = ln(x)(1) = ln x

Problem 2
ln x = ln(x +1) -1
logarithm of any number to the base of same number =1
so 1 can be written as ln(e) to the base e
ln(x) = ln(x + 1) - ln(e)
ln(x) = ln[(x +1)/(e)] ---- applying quotient rule
taking out logarithms
x = (x + 1)/e
cross multiplying
ex = x + 1
ex - x = 1
x(e - 1) = 1
x = 1/(e - 1)

2007-08-26 13:15:26 · answer #3 · answered by mohanrao d 7 · 0 0

Generally not.
But if it is an equation, then you have a specific value of x that satisfies ln x = ln (x+1) - 1 (at x = .58197671).
-----------
Ideas to solve the equation:
Collect variable terms in one side,
ln(x+1) - ln(x) = ln(1+1/x) = lne
1+1/x = e
x = 1/(e-1) = .58197671

2007-08-26 12:41:07 · answer #4 · answered by sahsjing 7 · 1 1

no,it's not. ln(x+1) is not equal to ln(x) = ln(1)


second problem:
ln (x) = ln (x+1) - 1

subtract ln(x + 1) for both sides
ln(x) - ln(x+1) = -1

quotient rule: ln(a) - ln(b) = ln(a/b)
ln [ x/(x+1)] = -1

raise the equations with the power or e
e^(ln [ x/(x+1)] = e^-1

memorise this rule;
e^(ln(x)) = x

x/(x+1) = 1/e

ex = x+1

ex - x = 1

x(e - 1) = 1

x = 1/(e-1)

2007-08-26 12:46:38 · answer #5 · answered by      7 · 0 0

no it is not. However, the ln(x*1) is equal to ln(x) +ln (1).

I would suggest doing:
lnx +1 = ln(x+1)
lnx + ln(e) = ln (x+1)
ln (ex) = ln(x+1)

and playing with it from there

2007-08-26 12:46:49 · answer #6 · answered by RunnerGrl 2 · 0 0

No, it is not.

ln(x) = ln(x + 1) - 1
ln(x+1) - ln(x) = 1
ln[(x+1)/x] = 1 (ln(a) - ln(b) = ln(a/b), that you can do)
(x+1)/x = exp(1) = e
x + 1 = ex (e times x)
1 = (e -1)x
x = 1/(e - 1)

2007-08-26 12:43:59 · answer #7 · answered by jcsuperstar714 4 · 0 0

ln x = ln (x+1) -1

ln (x+1) - ln x = 1

ln { (x+1)/ x} = 1

(x+1)/ x = ln inv 1

1+ 1/x = 2.72
1/x = 1.72
x = 0.58

2007-08-26 12:45:45 · answer #8 · answered by Anonymous · 0 0

ln(x+1) is not equal to lnx+ln1.

lnx=ln(x+1)-1
ln[(x+1)/x]=1
(x+1)/x=e
x+1=ex

(e-1)x=1
x=1/(e-1). ANS.

2007-08-26 12:52:30 · answer #9 · answered by Anonymous · 0 0

ln x = ln(x+1) - 1
e^(ln x) = e^(ln (x+1) - 1)
x = e^(ln(x+1)*e^(-1)
x = (x+1)/e
ex = x + 1
ex - x = 1
x (e -1) = 1
x = 1/(e-1)

2007-08-26 12:45:35 · answer #10 · answered by Demiurge42 7 · 0 0

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