Find the positive and negative domains of the function below:
Then determine for which values of the following is true:
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Find the positive and negative domains of the function below:
Then determine for which values of the following is true:
To solve this problem, we will determine where the function, given as , is positive.
Step 1: **Find the Roots**
Set the function equal to zero: . This yields:
- which gives , and
- which gives .
Thus, the roots are and .
Step 2: **Analyze Sign Intervals**
The parabola opens downwards because the product has a negative coefficient as the leading term.
We have intervals: , , and .
Since the quadratic opens downwards, it is positive between the roots (-4\frac{1}{9}, -\frac{1}{6}), where .
Therefore, the solution for the values of for which is:
The graph of the function below intersects the X-axis at points A and B.
The vertex of the parabola is marked at point C.
Find all values of \( x \) where \( f\left(x\right) > 0 \).
The second factor (-x - 4⅑) has a negative coefficient for x. When expanded, this gives a negative coefficient for the term, making the parabola open downward.
Since the parabola opens downward, it's positive between the roots and negative outside them. Test a point like x = -0.2 (which is between -4⅑ and -⅙) to confirm.
Convert to decimals: and . So -4⅑ is much smaller (more negative) than -⅙.
The inequality asks for f(x) > 0, which means strictly greater than zero. At the roots x = -4⅑ and x = -⅙, the function equals zero, not greater than zero.
Pick any number in your interval and substitute it. For example, try x = -0.3: should be true.
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