Solving for x: "1/2*log(5)(x^2-1)=1/4+1/2log(5)(x-1)

  • Thread starter parabol
  • Start date
In summary, the conversation was about solving the equation 1/2*log(5)(x^2-1)=1/4+1/2log(5)(x-1) for x, which involved manipulating the logarithms and simplifying the expression (x^2-1)/(x-1). The solution was to factor the numerator and cancel out common terms in order to obtain a single value for x.
  • #1
parabol
17
0

Homework Statement



1/2*log(5)(x^2-1)=1/4+1/2log(5)(x-1)

I have put the base to the log in the first set of brackets following log.

The question is simply solve for x the equation

The Attempt at a Solution



I firstly moved the logs onto the smae side and then multiplied both sides by1/2 (not shown) thus giving

log(5)(x^2-1)-log(5)(x-1)=1/2

log(5)((x^2-1)/(x-1))=1/2

Am i right in the saying the follwoing is the next step?

(x2-1)/(x-1)=5^(1/2)

If I am then can someone please help me understand how I am supposed to simplify the equaiton down to give a single x.

Thanks in advance.
 
Physics news on Phys.org
  • #2


Assuming that log(5) is log5, that is right. How can you rewrite
[tex]\frac{x^2-1} {x-1}[/tex]

specifically the numerator?
 
  • #3
That was exactly what I meant with regards to the base of the log.

I'm sorry I don't follow. I think I am looking to hard into this problem as I can see no way of simplifying (x2-1)/(x-1)
 
  • #4
Do you know how to factor x2 - 1?
 
  • #5
You have
[tex]\frac{x^2- 1}{x- 1}= \sqrt{5}[/tex]

What Bohrok is suggesting is that you factor the numerator. There is a simple cancelation.
 
  • #6
All sorted now.

Thanks very much for the sanity checks with this.
 

1. What does "Solving for x" mean in this equation?

Solving for x means finding the value or values of x that make the equation true.

2. How do I solve for x in this equation?

To solve for x, you will need to use algebraic techniques such as isolating the variable, combining like terms, and applying inverse operations.

3. What is the purpose of the logarithm in this equation?

The logarithm is used to solve for x because it allows us to rewrite the equation in a way that makes it easier to isolate the variable.

4. Can this equation have more than one solution for x?

Yes, it is possible for this equation to have more than one solution for x. This can happen when the equation contains logarithms, as logarithms can have multiple inputs that result in the same output.

5. Are there any restrictions on the possible values of x in this equation?

Yes, there are restrictions on the possible values of x in this equation. Since logarithms cannot take negative inputs, the expressions inside the logarithms must be positive. Additionally, the expression inside the first logarithm cannot equal 1, as this would result in an undefined answer for x.

Similar threads

  • Precalculus Mathematics Homework Help
Replies
4
Views
341
  • Precalculus Mathematics Homework Help
Replies
10
Views
599
  • Precalculus Mathematics Homework Help
Replies
3
Views
238
  • Precalculus Mathematics Homework Help
Replies
3
Views
751
  • Precalculus Mathematics Homework Help
Replies
1
Views
862
  • Precalculus Mathematics Homework Help
Replies
8
Views
765
  • Precalculus Mathematics Homework Help
Replies
10
Views
282
  • Precalculus Mathematics Homework Help
Replies
8
Views
801
  • Precalculus Mathematics Homework Help
Replies
10
Views
1K
Back
Top