Question

Answer the question for the function f(x) = log10 x

Find the ratio of a to b when f(a) = 5 + f(b).

Answer 1

$f(a)=lg(a) \ f(b)=lg(b)\lg(a)=5+lg(b) \ lg(a)-lg(b)=5 \ lg frac{a}{b} =5 \ frac{a}{b} =10^5$

Answer 2

 $f(x)=lgx\ lga=5+lgb\ lg(frac{a}{b})=5\ frac{a}{b}=10^5$