Question - Domain and Range Determination for Given Functions

Untuk soal (a):

D_{f(x,y)} = \{(x, y) \in \mathbb{R}^2 | x^2 - y^2 - 9 \geq 0\}

R_{f(x,y)} = \{f(x,y) \in \mathbb{R} | f(x,y) = 4-x^2-y^2 + \frac{1}{2}\log(x^2 - y^2 - 9), (x, y) \in D_{f(x,y)} \}

Untuk soal (b):

D_{f(x,y)} = \{(x, y) \in \mathbb{R}^2 | x^2 + y^2 - 1 \neq 0\}

R_{f(x,y)} = \{f(x,y) \in \mathbb{R} | f(x,y) = \frac{\sqrt{x^2 - y^2}}{x^2 + y^2 - 1}, (x, y) \in D_{f(x,y)} \}