Cal
posted by Zac .
Express the given quantity in a single logarithm.
ln(a + b) + ln(a  b)  2 ln c

The sum of two logarithms is equal to the logarithm of the product, and the difference equals the quotient:
log(A)+log(B)log(C)
=log(AB/C)
Twice the logarithm of a quantity is the logarithm of the square of the quantity:
2log(C)=log(C²)
So if we put it all together, we get:
log(A)+log(B)2log(C)
=log( AB/C²)