document.write( "Question 771697: I hope someone can clarify this. I'M CONFUSED!!!\r
\n" ); document.write( "\n" ); document.write( "2(log4 x + logx 4)=5\r
\n" ); document.write( "\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\r
\n" ); document.write( "\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\r
\n" ); document.write( "\n" ); document.write( "when m=2,
\n" ); document.write( "log4 x = m
\n" ); document.write( "log4 x = 2
\n" ); document.write( "x = 64\r
\n" ); document.write( "\n" ); document.write( "when m=1/2,
\n" ); document.write( "log4 x = m
\n" ); document.write( "x=2\r
\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
\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\r
\n" ); document.write( "\n" ); document.write( "when m=2,
\n" ); document.write( "log4 x = m
\n" ); document.write( "log4 x = 2
\n" ); document.write( "x = 64\r
\n" ); document.write( "\n" ); 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" ); document.write( "

Algebra.Com's Answer #470374 by Alan3354(69443)\"\" \"About 
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( "
\n" );