Event \(E_1\): getting numbers less than 3 = \{1, 2\}
Event \(E_2\): getting numbers greater than 3 = \{4, 5, 6\}
They are not complementary as they don't cover all possible outcomes.
Complementary events together cover the entire sample space.
Here, missing number 3.
So, Assertion (A) is false.
But Reason (R) is a true statement on complementary event property.