Evaluate log3 81
Let's set the expression equal to a variable, like x
.
log₃ 81 = x
Our goal is to find the value of x
.
The fundamental relationship between logarithms and exponents is:
logₐ b = c
is the same as aᶜ = b
Using this rule, we can rewrite our equation log₃ 81 = x
:
3ˣ = 81
Now, the problem is much simpler: we just need to find the power x
that makes this equation true.
We need to figure out how many times we multiply 3 by itself to get 81. Let's try it out:
We found it! 3 raised to the power of 4 is 81.
Since we found that 3⁴ = 81
, we can substitute 4 back in for x
.
x = 4
Therefore:
log₃ 81 = 4