Problem

Calculate the domain and range for this equation $y^{2}=-2(x-20)\{x> 10.4\}$

Answer

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Answer

Thus, the domain is \((10.4, 20]\) and the range is \(\boxed{[-\sqrt{19.2}, \sqrt{19.2}]}\).

Steps

Step 1 :First, we need to find the domain of the function. Since the function is defined for \(x > 10.4\), the domain is \((10.4, \infty)\).

Step 2 :Next, we find the range of the function. We have \(y^2 = -2(x - 20)\), so \(y^2 = -2x + 40\).

Step 3 :Since \(y^2\) is always nonnegative, we must have \(-2x + 40 \ge 0\), which gives us \(x \le 20\).

Step 4 :Combining this with the domain, we have \(10.4 < x \le 20\).

Step 5 :Now, we can rewrite the equation as \(y^2 = 40 - 2x\).

Step 6 :Since \(y^2\) is always nonnegative, the minimum value of \(y^2\) is 0, which occurs when \(x = 20\). Thus, the minimum value of \(y\) is 0.

Step 7 :The maximum value of \(y^2\) occurs when \(x = 10.4\), which gives us \(y^2 = 40 - 2(10.4) = 19.2\). Thus, the maximum value of \(y\) is \(\sqrt{19.2}\).

Step 8 :Since \(y^2\) can take on any value between 0 and 19.2, the range of \(y\) is \([-\sqrt{19.2}, \sqrt{19.2}]\).

Step 9 :Thus, the domain is \((10.4, 20]\) and the range is \(\boxed{[-\sqrt{19.2}, \sqrt{19.2}]}\).

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