Help: Simple Algebra yet I fail

  • Context: High School 
  • Thread starter Thread starter Curl
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    Algebra
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Discussion Overview

The discussion revolves around transforming one algebraic expression into another, specifically focusing on the manipulation of logarithmic terms. The context is primarily homework-related, as participants seek guidance on how to perform the transformation step-by-step.

Discussion Character

  • Homework-related, Mathematical reasoning

Main Points Raised

  • One participant expresses confusion about how to transform expression 1 into expression 2, indicating a lack of understanding of the necessary steps.
  • Another participant suggests adding a specific term, B*ln(f) - B*ln(f), to the top of the expression to facilitate the transformation.
  • A third participant acknowledges the possibility of showing the equivalence but notes that it is not extremely easy, emphasizing the importance of understanding the logarithmic identity ln(a) - ln(b) = ln(a / b).
  • This participant also recommends starting by expanding the brackets and suggests a method of adding zero in a specific form to aid in the transformation.

Areas of Agreement / Disagreement

Participants do not reach a consensus on a single method for the transformation, as multiple approaches are suggested, and the complexity of the task is acknowledged.

Contextual Notes

Some assumptions about logarithmic properties and algebraic manipulation techniques are implicit in the discussion, but these are not fully explored or resolved.

Curl
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How can I go from expression 1 to expression 2? Its easy to "show" they are equivalent, but if you started with 1, how will I get to 2? I got no clue how to transform it.



1
[ (A-B)*ln(c)+( B*ln(d)-A*ln(f) ) ] /ln(d/f)

2
(A-B)*ln(c/f)/ln(d/f)+B

I bet it's cake and I'm dumb.
 
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Hi Curl! :smile:

Add B*ln(f) - B*ln(f) to the top. :wink:
 
It is possible to show this, although it is not extremely easy.
One thing you do need is that
ln(a) - ln(b) = ln(a / b).

I suggest to start by opening up the "square" brackets.
You can also add 0, in the form (A - B) ln(f) - (A - B) ln(f) = A ln(f) - B ln(f) - (A - B) ln(f).
 
tiny-tim said:
Hi Curl! :smile:

Add B*ln(f) - B*ln(f) to the top. :wink:

haha, so I was right:

I bet it's cake and I'm dumb.
 

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