Answer:
Step-by-step explanation:
The relation is x²+y²=r² with r being the radius
[tex]f(x)=y=\sqrt{r^2-x^2} \\\\domain(f(x))=[-r,r]\ or\ -r\leq x \leq r\\range(f(x))=[0,r]\ or\ 0\leq y \leq r\\\\\\\ g(x)=y=-\sqrt{r^2-x^2} \\domain(g(x))=[-r,r]\ or\ -r\leq x \leq r\\range(g(x))=[-r,0]\ or\ -r\leq y \leq 0\\\\[/tex]
