On the set (A={1,2,3,4,5,6}), relation (R) is defined by (aRb) when (a) and (b) give the same remainder on division by (3). Which is the equivalence class of (1)?

Correct answer: ({1,4})

Step 1: On division by (3), (1) leaves remainder (1). Step 2: In the given set, (4) also leaves remainder (1), so the class of (1) is ({1,4}). Step 3: While finding an equivalence class, use only the elements of the given set.