which of the following relations are functions from A={1,3,5,7,9} to B={1,2,3,4,5} `f={(3,2),(1,5),(5,1),(7,4),(9,5)}`

Explanation

To determine whether the relation \( f = \{(3,2), (1,5), (5,1), (7,4), (9,5)\} \) is a function from the set \( A = \{1, 3, 5, 7, 9\} \) to the set \( B = \{1, 2, 3, 4, 5\} \), we need to check the definition of a function.

### Step-by-Step Solution:

1. **Definition of a Function**: A relation \( f \) is a function from set \( A \) to set \( B \) if every element in \( A \) is related to exactly one element in \( B \). This means that for every \( x \in A \), there should be a unique \( y \in B \) such that \( (x,y) \in f \).

2. **Identify Elements in Relation**: We examine the pairs in the relation \( f \):
- \( (3,2) \)
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