If the parabola is bending upwards and its vertex is above the x-axis, then it is always positive.
If the parabola is bending upwards and its vertex is above the x-axis, then it is always positive.
To solve this problem, let's analyze the situation:
Given a quadratic function , if it opens upwards, a > 0.
The vertex form of the parabola is , where is the vertex.
If the vertex is above the x-axis, then k > 0.
First, let's restate what it means for a quadratic to be always positive:
This means the function has no real roots and y > 0 for all .
To ensure this, consider:
The discriminant helps determine if the parabola intersects the x-axis.
If \Delta < 0, there are no real roots, meaning the parabola doesn't cross the x-axis and stays entirely above it for all .
Given a > 0 and the vertex is above the x-axis (k > 0), it ensures the function stays y > 0.
Therefore, with k > 0 and a > 0, implies no x-intercepts, confirming the parabola is always positive.
The correct answer is: Correct
Correct