Finding the Unknown Variable in a System of Linear Equations

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Homework Statement
let ##x,y,z>1##, and ##m>1## so that ##log_{xy}m=9##

##log_{yz}m=18##

##log_{xyz}m=8##

find ##log_{xz}m##
Relevant Equations
logarithms
1593317158084.png


this is my working...
 
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chwala said:
Homework Statement:: let ##x,y,z>1##, and ##m>1## so that ##log_{xy}m=9##

##log_{yz}m=18##

##log_{xyz}m=8##

find ##log_{xz}##
Relevant Equations:: logarithms

View attachment 265398

this is my working...
find ##log_{xz}##
The problem statement is incomplete. ##\log_{xy}## of what?
This is like asking what is ##\sqrt{}##?
 
sorry let me amend the question...
 
find ##log_{xz}m##...i checked with my colleague, my solution is correct, i would be looking at probably an alternative approach. thanks
 
chwala said:
find ##log_{xz}m##...i checked with my colleague, my solution is correct, i would be looking at probably an alternative approach. thanks
You can transform this into a set of linear equations:
$$9x + 9y = 1, \ \ \ 18y + 18z = 1, \ \ \ 8x + 8y + 8z = 1$$
And you want to find ##a## such that:
$$ax + az = 1$$
 
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PeroK said:
You can transform this into a set of linear equations:
$$9x + 9y = 1, \ \ \ 18y + 18z = 1, \ \ \ 8x + 8y + 8z = 1$$
And you want to find ##a## such that:
$$ax + az = 1$$

let me check this out...
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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