Domain Max Min Bdb0Fb
1. **Problem Statement:**
Correct and solve the first problem: Find the domain, global maximum, and global minimum of the function $$f(x,y) = \sqrt{64 - x^2 - y^2}$$.
2. **Domain of the function:**
The function involves a square root, so the expression inside must be non-negative:
$$64 - x^2 - y^2 \geq 0$$
This implies:
$$x^2 + y^2 \leq 64$$
So, the domain is the disk centered at the origin with radius 8:
$$D = \{(x,y) \mid x^2 + y^2 \leq 64\}$$
3. **Finding global maximum and minimum:**
- Since the square root function is increasing, the maximum value of $$f$$ occurs when $$64 - x^2 - y^2$$ is maximized.
- The maximum of $$64 - x^2 - y^2$$ is 64, achieved at $$x=0, y=0$$.
- So, the global maximum is:
$$f(0,0) = \sqrt{64} = 8$$
- The minimum value occurs when $$64 - x^2 - y^2$$ is minimized within the domain, i.e., when $$x^2 + y^2 = 64$$.
- At the boundary, $$f(x,y) = \sqrt{0} = 0$$.
4. **Summary:**
- Domain: $$x^2 + y^2 \leq 64$$
- Global maximum: $$8$$ at $$(0,0)$$
- Global minimum: $$0$$ on the circle $$x^2 + y^2 = 64$$
5. **Additional notes:**
- The function is continuous and smooth inside the domain.
- The domain is a closed and bounded set, so the global extrema exist.