Logarithmic problem

[PurpleNight]

Hi, could someone help me with this calculation?

 

[skeeter]

change of base ...

[MATH]\log_a{b} = \frac{\log_c{b}}{\log_c{a}} = \sqrt{2}[/MATH]
let [MATH]c = \frac{b}{a}[/MATH]
see what you can do from here ...

 

[PurpleNight]

Thank you

 

[Steven G]

Go with the definition
[math]\log_a{b} = \sqrt(2) \implies a^{\sqrt{2}} = b[/math]
Now find b/a and ab in terms of just a. Plug this into the 2nd log and go from there.