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Question-196576




Question Number 196576 by sonukgindia last updated on 27/Aug/23
Commented by Frix last updated on 27/Aug/23
Infinite solutions for x, y ∈R  No solution for x, y ∈Z
$$\mathrm{Infinite}\:\mathrm{solutions}\:\mathrm{for}\:{x},\:{y}\:\in\mathbb{R} \\ $$$$\mathrm{No}\:\mathrm{solution}\:\mathrm{for}\:{x},\:{y}\:\in\mathbb{Z} \\ $$
Answered by AST last updated on 27/Aug/23
2^(2x) −2^y 3^y =2^(48) 3^(12) =2^y (2^(2x−y) −3^y )⇒y=48  ⇒4^x =48^(12) +6^(48) ⇒x=log_4 3^(12) +log_4 (3^(36) +1)+24  ⇒x+y=72+6log_2 3+log_4 (3^(36) +1)
$$\mathrm{2}^{\mathrm{2}{x}} −\mathrm{2}^{{y}} \mathrm{3}^{{y}} =\mathrm{2}^{\mathrm{48}} \mathrm{3}^{\mathrm{12}} =\mathrm{2}^{{y}} \left(\mathrm{2}^{\mathrm{2}{x}−{y}} −\mathrm{3}^{{y}} \right)\Rightarrow{y}=\mathrm{48} \\ $$$$\Rightarrow\mathrm{4}^{{x}} =\mathrm{48}^{\mathrm{12}} +\mathrm{6}^{\mathrm{48}} \Rightarrow{x}={log}_{\mathrm{4}} \mathrm{3}^{\mathrm{12}} +{log}_{\mathrm{4}} \left(\mathrm{3}^{\mathrm{36}} +\mathrm{1}\right)+\mathrm{24} \\ $$$$\Rightarrow{x}+{y}=\mathrm{72}+\mathrm{6}{log}_{\mathrm{2}} \mathrm{3}+{log}_{\mathrm{4}} \left(\mathrm{3}^{\mathrm{36}} +\mathrm{1}\right) \\ $$
Answered by sniper237 last updated on 27/Aug/23
Such numbers can′t exist!!!  4^x ≡1[3] ; 48^(12) ≡0[3]⇒ 1−6^y ≡0[3]  So  y=0. Then  4^x =1+48^(12)   48^(12) ≡0[2]⇒ 4^x ≡1[2]⇒x=0  But  4^0 −6^0 ≠48^(12) .
$${Such}\:{numbers}\:{can}'{t}\:{exist}!!! \\ $$$$\mathrm{4}^{{x}} \equiv\mathrm{1}\left[\mathrm{3}\right]\:;\:\mathrm{48}^{\mathrm{12}} \equiv\mathrm{0}\left[\mathrm{3}\right]\Rightarrow\:\mathrm{1}−\mathrm{6}^{{y}} \equiv\mathrm{0}\left[\mathrm{3}\right] \\ $$$${So}\:\:{y}=\mathrm{0}.\:{Then}\:\:\mathrm{4}^{{x}} =\mathrm{1}+\mathrm{48}^{\mathrm{12}} \\ $$$$\mathrm{48}^{\mathrm{12}} \equiv\mathrm{0}\left[\mathrm{2}\right]\Rightarrow\:\mathrm{4}^{{x}} \equiv\mathrm{1}\left[\mathrm{2}\right]\Rightarrow{x}=\mathrm{0} \\ $$$${But}\:\:\mathrm{4}^{\mathrm{0}} −\mathrm{6}^{\mathrm{0}} \neq\mathrm{48}^{\mathrm{12}} .\: \\ $$
Commented by AST last updated on 27/Aug/23
That′s if x,y∈Z
$${That}'{s}\:{if}\:{x},{y}\in\mathbb{Z} \\ $$

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