Differentiation help. *question below*
Can I have some help on this, please?
First, find the derivative (you'll need the product rule for this one):\[y=x^n\ln x~~\implies~~\frac{dy}{dx}=\cdots\] Then plug this result into the equation and check if it holds: \[\begin{align*}x(\cdots)&=x^n+ny\\ &=x^n+nx^n\ln x\end{align*}\]
\[\frac{ dy }{ dx }=nx ^{n-1}lnx + x ^{n-1}\]
Right, now sub that into the equation and see if you have an identity.
\[x(nx ^{n-1}lnx + x ^{n-1})\] Hmm, I don't see an identity :s
\[x\left(\color{red}{nx ^{n-1}lnx + x ^{n-1}}\right)\] Try distributing that black \(x\) to the other terms.
\[n^{n-1} x^n \ln(x)+x^n\] ?
Close, that factor of \(n\) is not raised to anything.
\[nx^n \ln(x)+x^n\] is correct
Ah, I see
Hm, how do I proceed from here? @SithsAndGiggles
just realize that x^nlnx=y replace that by y and you get what you want
Thank you so much!
Wow :D
welcome!
Math is so much awesome than WOW!
haha!
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