If x4≤f(x)≤x2 for x in [−1,1] and x2≤f(x)≤x4 for x < -1 and x > 1, at what points c do you automatically know limx→cf(x) ? What can you say about the value of the limit at these points?
Q. If x4≤f(x)≤x2 for x in [−1,1] and x2≤f(x)≤x4 for x<−1 and x>1, at what points c do you automatically know limx→cf(x) ? What can you say about the value of the limit at these points?
Given Inequality: We are given that x4≤f(x)≤x2 for x in [−1,1]. This means that as x approaches any c within [−1,1], f(x) is squeezed between x4 and x2, which both approach c4 and x0 respectively.
Squeeze Theorem Application: Since both x4 and x2 are continuous functions and they are equal at x=c for any c in [−1,1], by the Squeeze Theorem, the limit of f(x) as x approaches c is also c2.
Limit Determination: For x < -1 and x > 1, we have x2≤f(x)≤x4. However, this does not help us determine the limit at any specific point c because the functions x2 and x4 do not approach the same value as x approaches any c outside of [−1,1].
Conclusion: Therefore, we automatically know the limit of f(x) as x approaches any c within the interval [−1,1], and the value of the limit is c2.
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