If f(x)=ln(ln(x)) find f′(6) ,correct to at least five decimal places.

Question

f’(6)=

Answer 1

f'(x) = [ln(lnx)]'

= (1/lnx)(lnx)'

= (1/lnx)(1/x)

= 1/xlnx

f'(6) = 1/6ln6

= about but ever slightly less than 0.09302

rounded off to 5 decimal places