If log5=a and log36=b, determine an expression for log $\displaystyle 6/25$ in terms of a and b

I can get the log5 side, as 2a, but i can't seem to get the other side, is the expression wrong, or am i just confused, i can't seem to get 36log6,

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- May 31st 2010, 07:28 PMnuckerslog expressions
If log5=a and log36=b, determine an expression for log $\displaystyle 6/25$ in terms of a and b

I can get the log5 side, as 2a, but i can't seem to get the other side, is the expression wrong, or am i just confused, i can't seem to get 36log6, - May 31st 2010, 07:34 PMsa-ri-ga-ma
- May 31st 2010, 07:51 PMnuckers
- May 31st 2010, 07:58 PMsa-ri-ga-ma
- May 31st 2010, 08:02 PMundefined
log(6/25) = log(6) - log(25)

Using sa-ri-ga-ma's result, log(6) = b/2

Now for the other part,

a = log(5) = (1/2)(2 log(5)) = (1/2)log(25)

2a = log(25)

So combining, $\displaystyle \log\left(\frac{6}{25}\right) = \frac{b}{2}-2a$ - May 31st 2010, 08:21 PMnuckers
thanks guys, but i'm just not seeing it, maybe i've just looked at too much math today, maybe a good nights sleep will make it better