Autor Tema: Positive integers pair

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29 Mayo, 2023, 03:47 pm
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jacks

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The number of positive integers \[ x,y,z \] satisfying \[ x^{y^{z}}\cdot y^{z^{x}}\cdot z^{x^{y}}=5xyz \]

29 Mayo, 2023, 07:04 pm
Respuesta #1

Luis Fuentes

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Hola

The number of positive integers \[ x,y,z \] satisfying \[ x^{y^{z}}\cdot y^{z^{x}}\cdot z^{x^{y}}=5xyz \]

The equation is equivalent to:

\( x^{y^{z}-1}\cdot y^{z^{x}-1}\cdot z^{x^{y}-1}=5 \)

Since \( x,y,z \) are positive integers at least one of then must be \( 5 \). Suppose \( x=5 \). Then:

\( y^z-1=1\quad \Rightarrow{}\quad y^z=2\quad \Rightarrow{}\quad y=2,\quad z=1 \)

We obtain the solution \( (x,y,z)=(5,2,1) \). By the symmetry of the equation there are two other possibilities:

\( (x,y,z)=(1,5,2),(2,1,5) \)

Best regards.


05 Junio, 2023, 01:37 pm
Respuesta #2

jacks

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Thanks so much Admin Got it. :aplauso: