Question concerning possible typo on HW (Topology)

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The discussion centers on the equivalence of topological statements regarding two topologies, T1 and T2, on a set X. The user has established that if T1 is a subset of T2, then closed sets in T1 are also closed in T2. However, they express uncertainty about whether reversing the roles of T1 and T2 in the implications is a typographical error. The concept of contravariance is highlighted as crucial in understanding the relationship between open and closed sets in topology.

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  • Knowledge of the definitions of topologies T1 and T2 on a set X.
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I'm trying to prove the following Theorem.

Suppose T1 and T2 are topologies for X. The following are equivalent:

1. T1 is a subset of T2;

2. if F is closed in (X, T1), then F is closed in (X, T2);

3. if p is a limit point of A in (X, T2), then p is a limit point of A in (X, T1).

So far, I've shown 1 implies 2. However, I'm curious about the reversal of T1 and T2 in statements 2 and 3. Is there a typo? I'm tying to show 1 implies 3, but I'm having no luck. I'll try reversing statement 3 and seeing if that works. If anyone thinks that there is a typo, please let me know. Thanks!
 
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Topologies are about open things, usually, limit points are abut closed things. Taking complements, i.e. switching from open to closed changes the order of containment. This is called contravariance, and is very important. N.B. I've not checked you particular case, but am just explaining a general principle.
 

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