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Logarithmic equation

  • Thread starter kukki1990
  • Start date
  • #1
5
0

Homework Statement


Find the value of x


Homework Equations


log x - 1/2log(x-1/2) = log(x+1/2) - 1/2log(x+1/8)


The Attempt at a Solution


used the log a + log b = log a*b & log a - log b = loga/b

and got a cubic equation 4x^3-8x^2-4x-1 = 0

but the answer in the book is x=1
 

Answers and Replies

  • #2
rock.freak667
Homework Helper
6,230
31
Could you please show your steps on how you've obtained that polynomial?
 
  • #3
gabbagabbahey
Homework Helper
Gold Member
5,002
6
You should be getting a quadratic ([itex]3x^2-2x-1=0[/itex]) which will give you the correct answer. However, I can't tell you where you are going wrong until you show me your workings...
 

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