1. Evaluating a Logarithm

I'm having trouble evaluating this logarithm (I converted it to an exponential equation just to make it easier to read.)

3^y = pi

I've done a casual examination of the examples and problems I have (maybe 30 minutes of review) and I can't find an example where y isn't solvable by inspection.

2. Re: Evaluating a Logarithm

Originally Posted by bkbowser
I'm having trouble evaluating this logarithm (I converted it to an exponential equation just to make it easier to read.)

3^y = pi

I've done a casual examination of the examples and problems I have (maybe 30 minutes of review) and I can't find an example where y isn't solvable by inspection.

$\displaystyle 3^y=\pi$

$\displaystyle \ln{3^y}=\ln{\pi}$

$\displaystyle y\ln{3}=\ln{\pi}$
.
.
.

3. Re: Evaluating a Logarithm

Oh I think I've just been insisting that the process is in the wrong section.

3^y = pi

y log 3 = log pi

so y = (log pi)/(log 3)?

4. Re: Evaluating a Logarithm

Originally Posted by Also sprach Zarathustra
$\displaystyle 3^y=\pi$

$\displaystyle \ln{3^y}=\ln{\pi}$

$\displaystyle y\ln{3}=\ln{\pi}$
.
.
.

Ha, refresh failure. TYVM sir.

5. Re: Evaluating a Logarithm

Futher y = ln pi / ln 3 = ln pi - ln 3 if I am remembering correctly.

6. Re: Evaluating a Logarithm

Originally Posted by CalBear12
Futher y = ln pi / ln 3 = ln pi - ln 3 if I am remembering correctly.
Incorrect!

$\displaystyle \ln{\frac{a}{b}}=\ln{a}-\ln{b}$

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$\displaystyle \frac {\ln{ \pi}} { \ln {3} } = \log_3{\pi}$