Domain Range Cb665B
1. **State the problem:** Find the domain and range of the function $$f(x) = \sqrt{7x^2 + 25} + 9$$.
2. **Domain:** The domain of a function involving a square root requires the expression inside the root to be non-negative:
$$7x^2 + 25 \geq 0$$
Since $$7x^2 \geq 0$$ for all real $$x$$ and $$25 > 0$$, the sum $$7x^2 + 25$$ is always positive.
3. Therefore, the domain is all real numbers:
$$\text{Domain: } x \in \mathbb{R}$$
4. **Range:** The square root function outputs values $$\geq 0$$. The minimum value inside the root is when $$x=0$$:
$$7(0)^2 + 25 = 25$$
So the minimum value of the square root term is:
$$\sqrt{25} = 5$$
5. Adding 9 to this minimum gives the minimum value of $$f(x)$$:
$$5 + 9 = 14$$
6. Since $$\sqrt{7x^2 + 25}$$ increases without bound as $$|x|$$ increases, the range is all values $$y$$ such that:
$$y \geq 14$$
**Final answers:**
Domain: $$x \in \mathbb{R}$$
Range: $$y \geq 14$$