Chapter 7 - Exponential and Logarithmic Functions - 7-3 Logarithmic Functions as Inverses - Practice and Problem-Solving Exercises - Page 456: 21

$\log_4{2}=\frac{1}{2}$

Let $x=\log_4{2}.$ RECALL: $\log_{a}{y} = b \longleftrightarrow a^b = y.$ Use the definition above to convert the equation to an exponential equation and have $4^x=2.$ Write each side in base 2 to have $(2^2)^x=2 \\2^{2x}=2$ The bases are the same, so the exponents must be equal. Thus, $2x=1 \\x = \frac{1}{2}.$ Therefore $\log_4{2}=\frac{1}{2}.$