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 this problem, we need to determine when is greater than and less than zero.
Start by finding the roots of the equation:
Set :
Rearrange the equation to find:
Take the square root of both sides:
Solving these gives:
These roots divide the number line into three intervals:
Test each interval to determine where the function is positive or negative:
For : Choose
Then:
So, in the interval .
For : Choose
Then:
So, in the interval .
For : Choose
Then:
So, in the interval .
Therefore, the positive domain is while the negative domain is .
Using the analysis above and applying it to the choices, the correct response is:
or
or
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
\( f\left(x\right) > 0 \).
Domain is all possible x-values you can input (for polynomials, that's all real numbers). Positive/negative regions tell you where the function's output is above or below zero.
The zeros are where the function equals zero, creating boundary points. These points divide the number line into intervals where the function is either entirely positive or entirely negative.
Pick any test value from each interval and substitute it into the function. If you get a positive result, that entire interval is positive. If negative, the whole interval is negative.
A quadratic can change sign at most twice because it has at most 2 zeros. The pattern is always: positive → negative → positive (or the reverse), creating at most 3 regions.
Remember: and . Use these decimal approximations to help visualize the intervals on a number line.
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