3 log in base 5 0.20
0.20 = 1/5 = 5^-1
log_5(5^-1) = -1
so, 3log_5(0.20) = -3
it helps to recall that for any base b,
logbbx = x
blogbx = x
log_5(5^-1) = -1
so, 3log_5(0.20) = -3
it helps to recall that for any base b,
logbbx = x
blogbx = x