Question

If A = { x : x ϵ N , x < 5 and x > 7 } , then n (A) is​

Answer 1

Answer:

State whether given set is empty or not?

{x:x is a natural numbers, x<5 and x>7}

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ANSWER

Solution:- Empty

Empty set (ϕ): which has no elements

Natural numbers =1,2,3,4,...........

Natural numbers less than 5, (x<5)=1,2,3,4

Natural numbers greater than 7, (x>7)=8,9,10,.........

∵ A number can not be simultaneously less than 5 and greater than 7.

Hence, the set of natural numbers less than 5 and greater than 7 is empty.

Answer 2

Answer:

{5,6} answer set builder to roster form