Question

Find, if the following sets are singleton sets:

B = {y : 2y + 1 < 3 and y ∈ W}

Answer 1

B = {y :2y + 1 < 3 and y ∈ W}

2y + 1 < 3

⇒ 2y + 1 - 1< 3 -1 (Subtracting 1 from both sides)

⇒  2y < 2

⇒  y < `(2)/(2)` (Dividing both sides by 2)

⇒  y < 1

∴ B = {0}

Hence it is a singleton set.