Answer:
Domain:— [ x ≥ -2, x ≤ -3 ]
Range:— [ y ≥ 0 ]
Step-by-step explanation:
You may use graphing calculator to draw a graph and examine the graph’s domain and range. However, I’ll explain further about the graph of quadratic in a surd.
First, factor the quadratic expression in the surd:—
![\displaystyle \large{f(x)=\sqrt{(x+3)(x+2)}}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Clarge%7Bf%28x%29%3D%5Csqrt%7B%28x%2B3%29%28x%2B2%29%7D%7D)
We can find the x-intercepts by letting f(x) = 0.
I’ll be separating in two parts — one for finding x-intercept and one for finding y-intercept.
__________________________________________________________
Finding x-intercepts
Let f(x) = 0.
![\displaystyle \large{0=\sqrt{(x+3)(x+2)}}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Clarge%7B0%3D%5Csqrt%7B%28x%2B3%29%28x%2B2%29%7D%7D)
Solve for x, square both sides:—
![\displaystyle \large{0^2 = (\sqrt{(x+3)(x+2)})^2}\\\displaystyle \large{0=(x+3)(x+2)}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Clarge%7B0%5E2%20%3D%20%28%5Csqrt%7B%28x%2B3%29%28x%2B2%29%7D%29%5E2%7D%5C%5C%5Cdisplaystyle%20%5Clarge%7B0%3D%28x%2B3%29%28x%2B2%29%7D)
Simply solve a quadratic equation:—
![\displaystyle \large{x=-3,-2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Clarge%7Bx%3D-3%2C-2%7D)
Therefore, x-intercepts are:—
![\displaystyle \large{\boxed{x=-3,-2}}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Clarge%7B%5Cboxed%7Bx%3D-3%2C-2%7D%7D)
__________________________________________________________
Finding y-intercept
Let x = 0.
![\displaystyle \large{f(x)=\sqrt{(0+3)(0+2)}}\\\displaystyle \large{f(x)=\sqrt{3 \cdot 2}}\\\displaystyle \large{f(x)=\sqrt{6}}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Clarge%7Bf%28x%29%3D%5Csqrt%7B%280%2B3%29%280%2B2%29%7D%7D%5C%5C%5Cdisplaystyle%20%5Clarge%7Bf%28x%29%3D%5Csqrt%7B3%20%5Ccdot%202%7D%7D%5C%5C%5Cdisplaystyle%20%5Clarge%7Bf%28x%29%3D%5Csqrt%7B6%7D%7D)
Therefore, y-intercept is:—
![\displaystyle \large{\boxed{\sqrt{6}}}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Clarge%7B%5Cboxed%7B%5Csqrt%7B6%7D%7D%7D)
__________________________________________________________
However, I want you to focus on x-intercepts instead. We know that the square root only gives you a positive value. That means the range of function can only be y ≥ 0.
For domain, first, we have to know how or what the graph looks like. You can input the function in a graphing calculator as you’ll see that when x ≥ -2, the graph heads to the right while/when x ≤ -3, the graph heads to the left. This means that the lesser value of x-intercept gets left and more value get right.
See, between -3 < x < -2, there is no curve, point or anything between the interval. Therefore, -3 < x < -2 does not exist in function.
Hence, the domain is:—
x ≥ -2, x ≤ -3