max{∣x∣−1,x2−1}≤min{x2−1,1−x},
where max{a,b}={a,b,if a≥bif a<b, and min{a,b}={b,a,if a≥bif a<b.
where , and .
Solution
It is clear that
so the inequality from the problem condition can be satisfied only if
and this, in turn, implies that
Therefore, , which means that . Also we should have that , and since we already know that , this can happen only if or , so or .
It is also easy to solve this problem using graphs (fig. 35). Here the graph of the left-hand side is drawn with dash-and-dash line, and the graph of the right-hand side – with dash-and-dot line. They intersect exactly at the specified values of .
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