I'm trying to combine this $$-\ln(a)-\ln(b)$$ into $$-\ln(\frac{a}{b})$$ but it doesn't seem to work like that. How would I combine the two logarithms into one? Thanks for the help!

# How to combine $-\ln(a)-\ln(b)$

algebra-precalculuslogarithms

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# How to combine $-\ln(a)-\ln(b)$

algebra-precalculuslogarithms

I'm trying to combine this $$-\ln(a)-\ln(b)$$ into $$-\ln(\frac{a}{b})$$ but it doesn't seem to work like that. How would I combine the two logarithms into one? Thanks for the help!

## Best Answer

If I factor out the $-1$ it's $(-1)(\ln(a)+\ln(b))$ which can be combined into $-\ln(ab)$ so $$-\ln(a)-\ln(b)=-\ln(ab)$$