Question

If a ⊆ b then prove that b' ⊆ a'

Answer 1

suppose s = (1,2,3,4,5,6,7,8) , a = (1,2,3,4)

b = (1,2,3,4,5,6)

=> so that a subset b

=> a'= (5,6,7,8)

=> b'= (7,8)

so that b' subset a'

hence proved...