Finding the Real Solution for Fractional Part Equations with Given Values of k

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The discussion focuses on solving the equation system where the fractional parts of x, x², and x³ are equal to a constant k, with k in the range [0, 1). It establishes that if {x} = k, then x can be expressed as x = ⌊x⌋ + k, where ⌊x⌋ is the floor of x. Similar expressions are derived for x² and x³, leading to the conclusion that all three equations must hold simultaneously. The thread suggests testing various values for k to find specific solutions. The conversation emphasizes the need for further guidance on how to proceed with the calculations.
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Calculation of Real ##x## in ##\{x\} = \{x^2\} = \{x^3\}##, Where ##\{x\} = ## fractional part of ##x##

My Try:: We Know that ##\{x\} ## and ##\{x^2\}## and ##\{x^3\}## are are ##\in \left[0,1\right)##

So Let we take ##\{x\} = \{x^2\} = \{x^3\} = k##, where ##k\in \left[0,1\right)##

So If ##\{x\} = k## , Then ##x-\lfloor x \rfloor = k\Rightarrow x = \lfloor x \rfloor +k##

where ##\lfloor x \rfloor = ## floor function of ##x##

Similarly If ##\{x^2\} = k## , Then ##x^2-\lfloor x^2 \rfloor = k\Rightarrow x^2 = \lfloor x^2 \rfloor +k##

Sililarly If ##\{x^3\} = k## , Then ##x^3-\lfloor x \rfloor = k\Rightarrow x^3 = \lfloor x^3 \rfloor +k##

Now How Can I proceed after that,

please Help me

Thanks
 
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Hint: test some values for k.
 
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Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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