Rewriting Expression w/Log Laws: x^10*sqrt((y^19)/(z^7))

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Homework Help Overview

The discussion revolves around rewriting the expression ln(x^10*sqrt((y^19)/(z^7))) using the laws of logarithms, specifically aiming to eliminate logarithms of products, quotients, or powers.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants explore the implications of the square root in logarithmic expressions, questioning how to correctly apply logarithmic laws to rewrite the given expression. There is an attempt to clarify the relationship between square roots and exponents, particularly the conversion of sqrt to a power of 1/2.

Discussion Status

Some participants have provided insights regarding the conversion of square roots to fractional exponents, and there is acknowledgment of the correct application of logarithmic properties. The discussion appears to be progressing towards a clearer understanding of the problem.

Contextual Notes

Participants are navigating through the application of logarithmic identities and are addressing potential misconceptions about the manipulation of logarithmic expressions involving products and powers.

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Homework Statement



Use the Laws of logarithms to rewrite the expression in a form with no logarithm of a product, quotient or power.
ln (x^10*sqrt((y^19)/(z^7))) = a ln(x)+b ln(y)+c ln(z)


Homework Equations



ln (x^a)=a ln(x)

The Attempt at a Solution



I know that it will start =10 ln(x), but I don't know what the square root implies. To specify, if I had the equation ln(sqrt(xy)), I thought the answer would be ln(x)+2 ln(y), but this isn't the case. Can anyone explain what happens to the square root when rewriting this expression? Thanks for your help!
 
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Taking the square root of a quantity is the same as raising that quantity to the 1/2th power. In other words, the square root is interchangeably just an exponent of 1/2.

- Warren
 
3.141592654 said:

Homework Statement



Use the Laws of logarithms to rewrite the expression in a form with no logarithm of a product, quotient or power.
ln (x^10*sqrt((y^19)/(z^7))) = a ln(x)+b ln(y)+c ln(z)


Homework Equations



ln (x^a)=a ln(x)
Another very relevant equation for this problem is ln(ab)= ln(a)+ ln(b).

The Attempt at a Solution



I know that it will start =10 ln(x), but I don't know what the square root implies. To specify, if I had the equation ln(sqrt(xy)), I thought the answer would be ln(x)+2 ln(y), but this isn't the case. Can anyone explain what happens to the square root when rewriting this expression? Thanks for your help!
As chroot told you sqrt is "1/2" power. Notice that even if you had 2nd power, you would NOT have ln((xy)2)= ln(x)+ 2 ln(y). ln((xy)[2= 2ln(xy)= 2[ln(x)+ ln(y)]= 2ln(x)+ 2ln(y).

Now, ln(sqrt(xy))= ln((xy)1/2)= what?
 
thanks for your help, both of you, I was able to figure out the problem with this!
Halls of Ivy,
ln(sqrt(xy))= ln((xy)1/2)= 1/2ln(xy)= 1/2ln(x)+ 1/2ln(y)
 
Exactly!
 

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