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Derivitive with ln - don't understand

  • Thread starter zeion
  • Start date
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1. Homework Statement

Differentiate the following:
y = ln(2x^2 - 2) / x^2 - 1



3. The Attempt at a Solution

The answer is y' = -ln(2x^2 - 2)(2x)(x^2 - 1)^-2 + 4x / 2x^2 - 2 (x^2 - 1)^-1

I understand all of it except 4x / 2x^2 - 2, how does ln(2x^2 - 2) derive into 4x / 2x^2 - 2?
 

rock.freak667

Homework Helper
6,230
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[tex]\frac{d}{dx}(ln(f(x))=\frac{f'(x)}{f(x)}[/tex]
 
467
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Oh okay, thanks, never seen that one before.
 

Hurkyl

Staff Emeritus
Science Advisor
Gold Member
14,847
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Oh okay, thanks, never seen that one before.
If you look closely, you'll notice that's just the chain rule....
 
467
0
Really? How?
 
11
0
To see how it is the chain rule, think about what the derivative of ln x is.
 

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