Question

Let f(x,y) = 4-√(x²+y²) and z = f(x,y) be a surface in ℝ³. What is the largest possible domain for f(x,y)? What is the corresponding range?

Answer 1

the range will be all real nos.
\[x,y \in (-\infty , \infty )\] and the range will be same.