Find the positive and negative domains of the function below:
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Find the positive and negative domains of the function below:
To solve for the positive and negative domains of the function , we follow these steps:
Let's calculate the discriminant: .
Since the discriminant is zero, we have a repeated root, which means the graph touches the x-axis at one point.
The root is found as follows:
.
This root represents a vertex-touching parabola, with no intervals of such that .
To find the positive domain (), we note the parabola opens upwards (since ) and only touches the x-axis at one point . Thus, the positive domain is .
The function does not take any negative values, since it opens upwards and only touches the x-axis.
Therefore, the positive domain is and the negative domain is none.
In conclusion, the solution to the problem is:
none
none
The graph of the function below intersects the X-axis at points A and B.
The vertex of the parabola is marked at point C.
Find all values of \( x \) where \( f\left(x\right) > 0 \).
The positive domain means all x-values where y > 0 (the function output is positive). It's about the function's values, not whether x is positive!
Since the parabola opens upward and only touches the x-axis at x = 1, the function is positive everywhere except at x = 1 where y = 0. So y > 0 for all x except x = 1.
Look at the coefficient of ! Since a = 2 > 0, the parabola opens upward. If a < 0, it would open downward.
With a positive discriminant, you'd get two distinct roots. The parabola would cross the x-axis twice, creating intervals where y > 0 and y < 0.
Since this upward-opening parabola only touches the x-axis at one point, it never goes below the x-axis. Therefore, y is never negative - only positive or zero.
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