The mathematical expression 9 ∉ t means: 9 union t 9 intersection t 9 is an element of t 9 is not an element of t

The correct option is 4.

Step-by-step explanation:

The given mathematical expression is

9 ∉ T

The meaning of mathematical signs are

∉ → means does not belongs to

∈ → belongs to

∪ → Union

∩ → Intersection

1. 9 union T is written as 9 ∪ T.

2.9 intersection T is written as 9 ∩ T.

3. 9 is an element of T is written as 9 ∈ T.

4. 9 is not an element of T is written as 9 ∉ T.

Therefore option 4 is correct.

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