Let the maximum number among the real numbers be , and the minimum number be . Given real numbers and that the three numbers can form the sides of a triangle, if , then the range of is \_\_\_\_\_\_.
Solution
It is obvious that , and .
1. When , we have . The feasible region is defined by . Since the parabola intersects the lines and within the first quadrant at the points and respectively, we have .
2. When , . The feasible region is defined by . Since the parabola intersects the lines and within the first quadrant at the points and respectively, we have .
In summary, the range of is .
This problem examines the range of , involves knowledge of parabolas, and requires defining a new feasible region and finding the coordinates of the intersection points within the first quadrant as the key steps.
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