how would you use log which has a subscript of 2 5 to approximate log subscript 2 50 and log subscript 2 0.4?

Answer 1

log(2) 50 = log(2) [5^2*2] =2 log(2)5 + log(2) 2

log(2) 0.4 = log(2) (2/5) = log(2) 2 - log(2) 5

But log(2) 2 = 1, so
log(2) 50 = log(2) [5^2*2] = 2 log(2)5 + 1
and
log(2) 0.4 = log(2) (2/5) = 1 - log(2) 5