document.write( "Question 771697: I hope someone can clarify this. I'M CONFUSED!!!\r
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document.write( "2(log4 x + logx 4)=5\r
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document.write( "My working:
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document.write( "2(log4 x + logx 4)=5
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document.write( "(log4 x + logx 4)=5/2
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document.write( "log4 x + (1/log4 x)=5/2\r
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document.write( "Here is where my confusion is. I have 2 different workings.
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document.write( "#1.
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document.write( "log4 x + (1/log4 x)=5/2
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document.write( "Let log4 x = m
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document.write( "Thus,
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document.write( "m + 1/m = 5/2
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document.write( "[[(m^2)+1]/m]=5/2
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document.write( "(2m^2)+2=5m
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document.write( "(m-2)(2m-1)=0
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document.write( "m=2 or 1/2\r
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document.write( "when m=2,
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document.write( "log4 x = m
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document.write( "log4 x = 2
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document.write( "x = 64\r
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document.write( "when m=1/2,
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document.write( "log4 x = m
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document.write( "x=2\r
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document.write( "#2.
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document.write( "log4 x + (1/log4 x)=5/2
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document.write( "[(log4 x)^2 + (1)/log4 x]=5/2
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document.write( "[2(log4 x) + (1)/log4 x]=5/2
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document.write( "Let log4 x = m
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document.write( "Thus, (2m + 1)/m=5/2
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document.write( "4m + 2 =5m
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document.write( "m= 2\r
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document.write( "when m=2,
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document.write( "log4 x = m
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document.write( "log4 x = 2
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document.write( "x = 64\r
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document.write( "I rechecked again, the correct answer should be m=1/2 and thus x=2. Can anyone tell me where did i do wrong for #2 working? And can anyone guide me how to determine the correct answer for #1 working? Please help me. Your help is much appreciated. \n" );
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Algebra.Com's Answer #470374 by Alan3354(69443)![]() ![]() You can put this solution on YOUR website! I hope someone can clarify this. I'M CONFUSED!!! \n" ); document.write( "2(log4 x + logx 4)=5 \n" ); document.write( "My working: \n" ); document.write( "2(log4 x + logx 4)=5 \n" ); document.write( "(log4 x + logx 4)=5/2 \n" ); document.write( "log4 x + (1/log4 x)=5/2 \n" ); document.write( "Here is where my confusion is. I have 2 different workings. \n" ); document.write( "#1. \n" ); document.write( "log4 x + (1/log4 x)=5/2 \n" ); document.write( "Let log4 x = m \n" ); document.write( "Thus, \n" ); document.write( "m + 1/m = 5/2 \n" ); document.write( "[[(m^2)+1]/m]=5/2 \n" ); document.write( "(2m^2)+2=5m \n" ); document.write( "(m-2)(2m-1)=0 \n" ); document.write( "m=2 or 1/2 \n" ); document.write( "when m=2, \n" ); document.write( "log4 x = m \n" ); document.write( "log4 x = 2 \n" ); document.write( "x = 64 \n" ); document.write( "when m=1/2, \n" ); document.write( "log4 x = m \n" ); document.write( "x=2 \n" ); document.write( "=========================================================== \n" ); document.write( "#2. \n" ); document.write( "log4 x + (1/log4 x)=5/2 \n" ); document.write( "[(log4 x)^2 + (1)/log4 x]=5/2 **** You squared the 1st term for no reason. \n" ); document.write( "==================================== \n" ); document.write( "[2(log4 x) + (1)/log4 x]=5/2 \n" ); document.write( "Let log4 x = m \n" ); document.write( "Thus, (2m + 1)/m=5/2 \n" ); document.write( "4m + 2 =5m \n" ); document.write( "m= 2 \n" ); document.write( "when m=2, \n" ); document.write( "log4 x = m \n" ); document.write( "log4 x = 2 \n" ); document.write( "x = 64 \n" ); document.write( "I rechecked again, the correct answer should be m=1/2 and thus x=2. \n" ); document.write( " |