Answer
$\frac{1}{4}$$\log (x^2+y^2)$
Work Step by Step
$Expand$ $the$ $expression$:
$\log \sqrt[4]{x^2+y^2}$
Rewrite the fourth root
$\log (x^2+y^2)^\frac{1}{4}$
Apply the Third Law of Logarithms
$\log (x^2+y^2)^\frac{1}{4}$ = $\frac{1}{4}$$\log (x^2+y^2)$
You cannot take out the squares on x and y since x and y are being added
$\frac{1}{4}$$\log (x^2+y^2)$