Let A = {3, 5} and B = {7, 11}.
Let R = {(a, b) : ` a in A, b in B, a-b` is even}
Show that R is an universal relations from A into B.

Explanation

To show that the relation \( R \) is a universal relation from \( A \) into \( B \), we need to follow these steps:

### Step 1: Define the sets
We have two sets:
- \( A = \{3, 5\} \)
- \( B = \{7, 11\} \)

### Step 2: Determine the Cartesian product \( A \times B \)
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