MATHEMATICAL NOTATIONS

1. ≈ (Approximately Equal)
Usage: Indicates that two values are roughly the same, but not exactly equal.
Example: 𝜋 ≈3.14

2. ∝ (Proportional to)
Usage: Shows that one quantity is proportional to another.
Example: y∝x means that y is proportional to x, meaning as x increases, y increases in a similar manner.

3. ∅(Empty Set)
Usage: Denotes the empty set, which is a set that contains no elements.
Example: A=∅ means that set A has no elements.

4. ∪ (Union of Sets)
Usage: Represents the union of two sets, meaning all elements that are in either set.
Example: If A={1,2} and B={2,3}, then A∪B={1,2,3}.

5. ∩ (Intersection of Sets)
Usage: Represents the intersection of two sets, meaning all elements that are common to both sets.
Example: If A={1,2} and B={2,3}, then A∩B={2}.

6. ⊂ (Subset)
Usage: Denotes that one set is a subset of another, meaning all elements of the first set are also in the second set.
Example: If A={1,2} and B={1,2,3}, then A⊂B.

7. N (Natural Numbers)
Usage: Represents the set of natural numbers, which are the positive integers starting from 1 (or sometimes 0).
Example: N={1,2,3,4,…}.

8. Z (Integers)
Usage: Represents the set of integers, including all positive and negative whole numbers.
Example: Z={…,−3,−2,−1,0,1,2,3,…}.

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9. ∃ (There Exists)
Usage: Represents the word "there exists", used in statements asserting that at least one element satisfies a given condition.
Example: ∃x∈Z such that x=3 means "there exists an integer x such that x=3."

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