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bounce
Junior Member

Azerbaijan
3 Posts

 Posted - 05/14/2007 :  20:04:59 this is a basic concept and i can clearly see that the results are different but the theory of it eludes me, maybe because i used a calculator.......A machine design student noted that the edge of a robotic link was shaped like a logarithmic curve. Using a a graphing calculator the student viewed various logarithmic curves including y=log xand y= 2log x, for which the student thought would be identical, but a difference was observed, write a paragraph explaining the difference and why it occurs.now the graphs exhibit 2 different trends, for y = log xit appears that it exists for all negative and positive values of yfor y= 2logx it seems that it only exists for all positive values of y.but according to the text i'm studying they should be proportional to eachother and therefore have the same values, so why the difference in the graphs? any help here would be greatly appreciated

Subhotosh Khan

USA
9114 Posts

 Posted - 05/15/2007 :  07:25:02 quote:Originally posted by bouncethis is a basic concept and i can clearly see that the results are different but the theory of it eludes me, maybe because i used a calculator.......A machine design student noted that the edge of a robotic link was shaped like a logarithmic curve. Using a a graphing calculator the student viewed various logarithmic curves including y=log xand y= 2log x, for which the student thought would be identical, but a difference was observed, write a paragraph explaining the difference and why it occurs.now the graphs exhibit 2 different trends, for y = log xit appears that it exists for all negative and positive values of yfor y= 2logx it seems that it only exists for all positive values of y.but according to the text i'm studying they should be proportional to eachother and therefore have the same values, so why the difference in the graphs? any help here would be greatly appreciatedThis is because in realitylog(x2) = 2 * log(|x|)|x| = absolute value of xlog(x) is not defined in the real domain for negative x.Just like (x) is not defined in the real domain for negative x.thusThe graph of y = (x)2 is not identical to the graph of y = x

bounce
Junior Member

Azerbaijan
3 Posts

 Posted - 05/15/2007 :  23:25:34 quote:Originally posted by Subhotosh Khanquote:Originally posted by bouncethis is a basic concept and i can clearly see that the results are different but the theory of it eludes me, maybe because i used a calculator.......A machine design student noted that the edge of a robotic link was shaped like a logarithmic curve. Using a a graphing calculator the student viewed various logarithmic curves including y=log xand y= 2log x, for which the student thought would be identical, but a difference was observed, write a paragraph explaining the difference and why it occurs.now the graphs exhibit 2 different trends, for y = log xit appears that it exists for all negative and positive values of yfor y= 2logx it seems that it only exists for all positive values of y.but according to the text i'm studying they should be proportional to eachother and therefore have the same values, so why the difference in the graphs? any help here would be greatly appreciatedThis is because in realitylog(x2) = 2 * log(|x|)|x| = absolute value of xlog(x) is not defined in the real domain for negative x.Just like (x) is not defined in the real domain for negative x.thusThe graph of y = (x)2 is not identical to the graph of y = x

bounce
Junior Member

Azerbaijan
3 Posts

 Posted - 05/15/2007 :  23:28:10 quote:Originally posted by Subhotosh Khanquote:Originally posted by bouncethis is a basic concept and i can clearly see that the results are different but the theory of it eludes me, maybe because i used a calculator.......A machine design student noted that the edge of a robotic link was shaped like a logarithmic curve. Using a a graphing calculator the student viewed various logarithmic curves including y=log xand y= 2log x, for which the student thought would be identical, but a difference was observed, write a paragraph explaining the difference and why it occurs.now the graphs exhibit 2 different trends, for y = log xit appears that it exists for all negative and positive values of yfor y= 2logx it seems that it only exists for all positive values of y.but according to the text i'm studying they should be proportional to eachother and therefore have the same values, so why the difference in the graphs? any help here would be greatly appreciatedThis is because in realitylog(x2) = 2 * log(|x|)|x| = absolute value of xlog(x) is not defined in the real domain for negative x.Just like (x) is not defined in the real domain for negative x.thusThe graph of y = (x)2 is not identical to the graph of y = xthank you so very much for clarifying that for me.
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