**Set Operations**: Before we move further into Probability. Let us try to understand Set Operations briefly.

A **Set **is an unordered collection of objects, known as elements or members of the set. An element ‘a’ belong to a set A can be written as ‘a ∈ A’, ‘a ∉ A’ denotes that a is not an element of the set A.

**Basic Set Operations:**

**Union of two Sets: **Union of the sets A and B, denoted by A ∪ B, is the set of distinct element belongs to set A or set B, or both.

**Intersection of two Sets: **Intersection of the sets A and B, denoted by A ∩ B, is the set of elements belongs to both A and B i.e. set of common element in A and B.

**Independent Sets:** Two sets are said to be independent or disjoint if their intersection is the empty set .i.e. sets have no common elements.

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