>>>That's my daughter's math question. I couldn't solve that... :(
>>>
>>>f(x/y)=f(x)+f(y)
>>>f(10)=1
>>>f(10000)=?
>>
>>Obviously the idea is to find out what the function is. The form of the function reminds me strongly of a logarithm (log ab = log a + log b), except that we have a division here. Are you sure the first part is plus, and not minus?
>
>I asked my daughter again. You right, it was minus. Sorry...
In that case, the function is log (base 10), and log 10000 is 4. (For the log function, log xy = log x + log y, and log x/y = log x - log y.)
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)
