How do you differentiate f(x)=ln(x)^x?

1 Answer
Jan 20, 2016

f'(x) = ln^x(x)(1/ln(x)+ln(ln(x)))

Explanation:

Using implicit differentiation , the chain rule , and the product rule ,

Let y = ln^x(x)

=>ln(y) = ln(ln^x(x)) = xln(ln(x))

=>d/dxln(y) = d/dxxln(ln(x))

=>1/ydy/dx = x(d/dxln(ln(x))) + ln(ln(x))(d/dxx)

=x(1/(ln(x))(d/dxln(x))) + ln(ln(x))

=x(1/ln(x)(1/x)) + ln(ln(x))

= 1/ln(x) + ln(ln(x))

=> dy/dx = y(1/ln(x) + ln(ln(x)))

= ln^x(x)(1/ln(x) + ln(ln(x)))