Find the positive and negative domains of the function below:
Find the positive and negative domains of the function below:
To solve this problem, we need to analyze the function , which is a quadratic in vertex form.
Step 1: Identify the Vertex and Orientation
The function is given as , which is in the form . Here, and , meaning the vertex of the parabola is at . Because (which is positive), the parabola opens upwards.
Step 2: Determine the Minimum Value of
Since the parabola opens upwards, the minimum value of occurs at the vertex. At the vertex , the value of is 5.
Step 3: Analyze Positive and Negative Values of
The minimum value of is 5, which indicates that is always greater than zero. Thus, for all real values of , remains positive.
Conclusion:
Since the function has no negative values and is always positive:
x < 0 : none
x > 0 : all
Therefore, the positive and negative domains of the function are:
x < 0 : none
x > 0 : all
x < 0 : none
x > 0 : all