How do you simplify log 4 + log 5 - log 2log4+log5log2?

1 Answer
Apr 8, 2018

To answer this question, the following logarithm rules are needed:
loga+logb = log(a*b)loga+logb=log(ab)
loga - logb = log(a/b)logalogb=log(ab)
log_b b = 1logbb=1

Using the above rules:
log4 + log5 - log2log4+log5log2
=log((4*5)/2)=log(452)
= log(20/2)=log(202)
= log(10)=log(10)
Since the base of a normal loglog is 1010, log10 = 1log10=1 (as 10^1 = 10101=10).