Question 19124
Hello There:

To write an expression for log_5(9), we change the 9 into 3^2.  This allows us to use the property of logarithms which allows us to move the exponent into the coefficient position.  In other words, the property is:

log(a^x) = x*log(a)

So, we have:

log_5(9) = log_5(3^2) = 2*log_5(3).

We're given a decimal approximation for log_5(3); double it to find an approximation for log_5(9).

~ Mark