N nikchic5 Junior Member Joined Feb 16, 2006 Messages 106 Feb 26, 2006 #1 If anyone could help me with this one it would be great! Use logarithmic differentation to find the derivative. y= (x)^(ln x) If anyone could help me by showing me step-by-step it would be greatly appreicated!! Thank you soo much!
If anyone could help me with this one it would be great! Use logarithmic differentation to find the derivative. y= (x)^(ln x) If anyone could help me by showing me step-by-step it would be greatly appreicated!! Thank you soo much!
G galactus Super Moderator Staff member Joined Sep 28, 2005 Messages 7,203 Feb 26, 2006 #2 Try rewriting \(\displaystyle \L\\x^{ln(x)}\) as \(\displaystyle e^{(ln(x))^{2}}\) Use the chain rule. \(\displaystyle \L\\\frac{d}{dx}[e^{(ln(x))^{2}}]\) Take the derivative of \(\displaystyle \L\\(ln(x))^{2}=\frac{2ln(x))}{x}\) Since \(\displaystyle \L\\x^{ln(x)}=e^{(ln(x))^{2}}\), we have: \(\displaystyle \L\\y'=\frac{2ln(x)x^{ln(x)}}{x}\)
Try rewriting \(\displaystyle \L\\x^{ln(x)}\) as \(\displaystyle e^{(ln(x))^{2}}\) Use the chain rule. \(\displaystyle \L\\\frac{d}{dx}[e^{(ln(x))^{2}}]\) Take the derivative of \(\displaystyle \L\\(ln(x))^{2}=\frac{2ln(x))}{x}\) Since \(\displaystyle \L\\x^{ln(x)}=e^{(ln(x))^{2}}\), we have: \(\displaystyle \L\\y'=\frac{2ln(x)x^{ln(x)}}{x}\)
D daon Senior Member Joined Jan 27, 2006 Messages 1,284 Feb 26, 2006 #3 nikchic5 said: If anyone could help me with this one it would be great! Use logarithmic differentation to find the derivative. y= (x)^(ln x) If anyone could help me by showing me step-by-step it would be greatly appreicated!! Thank you soo much! Click to expand... 1. Take the Ln of both sides and simplify: \(\displaystyle Ln(y) = Ln(x^{Lnx})\) \(\displaystyle Ln(y) = Ln(x)Ln(x)\) \(\displaystyle Ln(y) = Ln^2(x)\) 2. Differentiate implicitly and simplify: \(\displaystyle \L\\ \frac{1}{y}\frac{dy}{dx} = \frac{2Ln(x)}{x}\) \(\displaystyle \L\\\frac{dy}{dx} = y[\frac{2Ln(x)}{x}]\) but, \(\displaystyle y=x^{Lnx}\) \(\displaystyle \L\\ \frac{dy}{dx} = [x^{Lnx}]\frac{2Ln(x)}{x}\)
nikchic5 said: If anyone could help me with this one it would be great! Use logarithmic differentation to find the derivative. y= (x)^(ln x) If anyone could help me by showing me step-by-step it would be greatly appreicated!! Thank you soo much! Click to expand... 1. Take the Ln of both sides and simplify: \(\displaystyle Ln(y) = Ln(x^{Lnx})\) \(\displaystyle Ln(y) = Ln(x)Ln(x)\) \(\displaystyle Ln(y) = Ln^2(x)\) 2. Differentiate implicitly and simplify: \(\displaystyle \L\\ \frac{1}{y}\frac{dy}{dx} = \frac{2Ln(x)}{x}\) \(\displaystyle \L\\\frac{dy}{dx} = y[\frac{2Ln(x)}{x}]\) but, \(\displaystyle y=x^{Lnx}\) \(\displaystyle \L\\ \frac{dy}{dx} = [x^{Lnx}]\frac{2Ln(x)}{x}\)
N nikchic5 Junior Member Joined Feb 16, 2006 Messages 106 Feb 26, 2006 #4 Thanks Thanks you both very much!