If a parabola is bending downwards and its vertex is below the x-axis, then it is always negative.
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If a parabola is bending downwards and its vertex is below the x-axis, then it is always negative.
The problem concerns a downward-opening parabola with a vertex below the x-axis. Let's elaborate on these terms to determine if the given statement is correct:
Therefore, the entire quadratic function is negative for all values of due to the vertex being the maximum and its y-coordinate being negative. Thus, the statement that such a parabola is always negative is indeed "correct".
Thus, the correct choice is: .
Correct
The graph of the function below does not intersect the \( x \)-axis.
The parabola's vertex is marked A.
Find all values of \( x \) where
\( f\left(x\right) > 0 \).
Look at the coefficient of ! If a < 0 in , the parabola opens downward like an upside-down U.
If the vertex is on the x-axis (k = 0), then the parabola touches the x-axis at exactly one point. The function equals zero at that point but is negative everywhere else.
Only if its vertex is above the x-axis! When the vertex (maximum point) is above the x-axis, part of the parabola will be positive before it crosses down to negative values.
Use the vertex formula: for the x-coordinate, then substitute to find for the y-coordinate.
Sign analysis helps you understand function behavior! Knowing when a quadratic is always positive, always negative, or changes sign is crucial for solving inequalities and real-world applications.
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