Logarithmic Differentation

nikchic5

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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!
 
Try rewriting \(\displaystyle \L\\x^{ln(x)}\) as e(ln(x))2\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:

\(\displaystyle \L\\y'=\frac{2ln(x)x^{ln(x)}}{x}\)
 
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!

1. Take the Ln of both sides and simplify:

Ln(y)=Ln(xLnx)\displaystyle Ln(y) = Ln(x^{Lnx})

Ln(y)=Ln(x)Ln(x)\displaystyle Ln(y) = Ln(x)Ln(x)

Ln(y)=Ln2(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, y=xLnx\displaystyle y=x^{Lnx}

\(\displaystyle \L\\ \frac{dy}{dx} = [x^{Lnx}]\frac{2Ln(x)}{x}\)
 
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