How do you differentiate (lnx)^(x)?

1 Answer
Dec 24, 2016

d/dx(lnx)^x = (lnx)^x{1/lnx + ln((lnx))}

Explanation:

Let y=(lnx)^x

Take (Natural) logarithms of both sided:

" " lny = ln((lnx)^x )
:. lny = xln((lnx) )

Differentiate Implicitly (LHS) and apply product rule and chain rule (RHS).

\ \ \ \ \ \ 1/ydy/dx = (x)(1/lnx*1/x) + (1)(ln((lnx))
:. \ 1/ydy/dx = 1/lnx + ln((lnx))
:. " " dy/dx = y{1/lnx + ln((lnx))}
:. " " dy/dx = (lnx)^x{1/lnx + ln((lnx))}