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...
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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