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Solve-log-2x-2-log-3x-2-log-2-2-log-3-2-




Question Number 121899 by ZiYangLee last updated on 12/Nov/20
Solve (log 2x)^2 +(log 3x)^2 =(log 2)^2 +(log 3)^2
$$\mathrm{Solve}\:\left(\mathrm{log}\:\mathrm{2}{x}\right)^{\mathrm{2}} +\left(\mathrm{log}\:\mathrm{3}{x}\right)^{\mathrm{2}} =\left(\mathrm{log}\:\mathrm{2}\right)^{\mathrm{2}} +\left(\mathrm{log}\:\mathrm{3}\right)^{\mathrm{2}} \\ $$
Commented by Dwaipayan Shikari last updated on 12/Nov/20
x=1  2log^2 x+2log2logx+2log3logx=0  log^2 x+logxlog6=0  logx=−log6⇒x=(1/6)    or logx=0 ,x=1
$${x}=\mathrm{1} \\ $$$$\mathrm{2}{log}^{\mathrm{2}} {x}+\mathrm{2}{log}\mathrm{2}{logx}+\mathrm{2}{log}\mathrm{3}{logx}=\mathrm{0} \\ $$$${log}^{\mathrm{2}} {x}+{logxlog}\mathrm{6}=\mathrm{0} \\ $$$${logx}=−{log}\mathrm{6}\Rightarrow{x}=\frac{\mathrm{1}}{\mathrm{6}}\:\:\:\:{or}\:{logx}=\mathrm{0}\:,{x}=\mathrm{1} \\ $$
Commented by ZiYangLee last updated on 12/Nov/20
thanks sir
$$\mathrm{thanks}\:\mathrm{sir} \\ $$
Answered by MJS_new last updated on 12/Nov/20
(log nx)^2 =(log x)^2 +2log n log x +(ln n)^2   transforming the given equation we get  log x log (6x) =0  ⇒ x=1∨x=(1/6)
$$\left(\mathrm{log}\:{nx}\right)^{\mathrm{2}} =\left(\mathrm{log}\:{x}\right)^{\mathrm{2}} +\mathrm{2log}\:{n}\:\mathrm{log}\:{x}\:+\left(\mathrm{ln}\:{n}\right)^{\mathrm{2}} \\ $$$$\mathrm{transforming}\:\mathrm{the}\:\mathrm{given}\:\mathrm{equation}\:\mathrm{we}\:\mathrm{get} \\ $$$$\mathrm{log}\:{x}\:\mathrm{log}\:\left(\mathrm{6}{x}\right)\:=\mathrm{0} \\ $$$$\Rightarrow\:{x}=\mathrm{1}\vee{x}=\frac{\mathrm{1}}{\mathrm{6}} \\ $$
Commented by ZiYangLee last updated on 12/Nov/20
Thanks sir..★
$$\mathrm{Thanks}\:\mathrm{sir}..\bigstar \\ $$

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