To determine which function is negative for the interval \([-1, 1]\), we can analyze the information provided for each of the three functions.
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First Function:
- Minimum at \((-1, -2)\)
- Crosses x-axis at \((-2.5, 0)\) and \((0.5, 0)\)
- Crosses y-axis at \((0, -1)\)
Within the interval \([-1, 1]\), the function has a minimum value at \((-1, -2)\), which is negative. It crosses the x-axis at \((0.5, 0)\), meaning that it is negative up to \(0.5\). Therefore, this function is negative for the entire interval \([-1, 1]\).
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Second Function:
- Minimum at \((0, -2)\)
- Crosses x-axis at \((-1.5, 0)\) and \((1.5, 0)\)
In this case, the function is negative at \(x = 0\) (where it has its minimum value of \(-2\)) and crosses the x-axis at \(-1.5\) and \(1.5\). Therefore, it stays negative on the interval \([-1, 1]\) as well.
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Third Function:
- Maximum at \((0, 2)\)
- Minimum at \((1.5, -2.75)\)
- Crosses x-axis at \((-0.6, 0)\) and \((0.6, 0)\)
This function has a maximum of \(2\) at \(x=0\), which is positive, and crosses the x-axis at points that suggest it is positive at \(x=0\). Therefore, this function cannot be negative over the interval \([-1, 1]\).
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Fourth Function:
- Maximum at \((-1.25, 4)\)
- Minimum at \((1.5, -3.5)\)
- Crosses x-axis at points including \((-1.75, 0)\), and \( (0.75, 0)\)
Since the function has a maximum of \(4\) at \((-1.25)\) and it crosses the x-axis before and after \(1\), the function can turn positive within the interval \([-1, 1]\).
Conclusion:
From this analysis, both the first function and the second function are negative over the interval \([-1, 1]\). However, considering we need to identify only one function accurate with its minimum, the first function is confirmed to be negative throughout the entire interval [−1, 1].