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, follow these steps:
Step 1: Find the roots of the function. Set .
Step 2: Rearrange and solve for : Solving gives , resulting in roots and .
Step 3: Determine the intervals: Step 4: Test each interval to check the sign of : \begin{itemize}
For and , becomes larger than 2, so is negative.
For , is less than 2, so is positive.
Thus, the function is negative for or , and positive for .
Therefore, the positive and negative domains of the function are:
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
\( f\left(x\right) > 0 \).
The zeros divide the number line into intervals where the function doesn't change sign. Think of it like crossing a bridge - the function can only change from positive to negative (or vice versa) at these crossing points!
Pick any test value in each interval and substitute it into the original function. If you get a positive result, that entire interval is positive. If negative, the whole interval is negative.
The negative sign flips the parabola upside down. Since is always positive, adding the negative makes it an inverted parabola that opens downward.
The question asks for separate domains where the function is positive vs negative. You need to identify all x-values where y > 0 (positive domain) and all x-values where y < 0 (negative domain).
Keep in exact form unless told to use decimals. The exact boundaries are and , which create three distinct intervals.
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