Find the cardinal number of the following sets :
(i)A1={−2,−1,1,3,5}
(ii)A2={x:x∈ N and 3 ≤x<7}
(iii)A3={p:p ∈ W and 2p−3 < 8}
(iv)A4={b:b∈Z and −7< 3b−1 ≤2} Cardinal~Number~of~set~:The number of elements in a set is called its Cardinal Number.
(i)A1={−2,−1,1,3,5} Cardinal number of set A1=5 Ans.
(ii)A2={x:x∈ N and 3 ≤x<7} ={3,4,5,6} ∴Cardinal number of set A2=4 Ans.
(iii)A3={p:p ∈ W and 2p−3 < 8}
2P-3<8
⇒ 2P<11⇒ P<112 (Dividing both sides by 2)⇒ P<5.5∴A3={0,1,2,3,4,5}∴ Cardinal Number of set A3=6Ans.
(iv)A4={b:b∈Z and −7< 3b−1 ≤2}
-7<3b-1
⇒ −7+1<3b−1+1 (Adding 1 to both sides)⇒ −6<3b⇒ −63