Fix Exercise 9.8.2 IVT counterexample statements#495
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teorth merged 1 commit intoteorth:mainfrom Apr 30, 2026
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rkirov
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I just did this chapter and made the same edits. LGTM.
teorth
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Apr 30, 2026
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This corrects the statements of the four Exercise 9.8.2 counterexamples.
The previous statements negated the existence of an intermediate value
y, and also duplicated the interval condition. This expressed that no intermediate value exists, rather than that an intermediate value has no preimage in[a,b].The updated statements follow the shape of Theorem 9.7.1: choose
ybetweenf aandf b, then assert that noc ∈ Set.Icc a bmaps toy.No exercise solutions are added; the proofs remain
sorry.Verified with:
lake build Analysis.Section_9_8