By using the logarithm laws,
lga+lgb=lgab
log a− log b=logba
we can collect together the terms into one logarithmic expression
ln8−ln4−ln2=ln8−ln4+ln2=ln8−ln42=ln842=ln1=0
where ln 1 =0, since e0=1 (the equality a0=1 holds for all a=0 ).
a
b
ba
ln4+ln2=ln8−ln42=ln842=ln1=0
=0