Question

evaluate

Answer 1

\[\int\limits_{e ^{9}}^{e ^{81}}\frac{ dx }{ x \sqrt{lnx} }\]

Answer 2

try \(u=\ln(x)\)

Answer 3

let say u = Inx
then take the derivative of u = ?

Answer 4

also notice how easy it is to change the limits of integration
\[u=\ln(x), u(e^9)=9\] and so on

Answer 5

is the derivative of u 1/x

Answer 6

can someone help me?