Question

If A={2,3,4,5,6,7} and {,7,8,9} then n (AUB) and n (A intersection B)

Answer 1

Step-by-step explanation:

A U B = { 2 , 3, 4, 5, 6, 7, 8, 9 }

n(A U B) = 8 [ Total no of elements ]

A ∩ B = { 7 }

n(A ∩ B ) = 1

hope it's useful to u plz mark me as brainliest

Answer 2

Answer:

$n(A\cup B)=8$ and $n(A\cap B)=1$

Step-by-step explanation:

Given the sets $A=\{2,3,4,5,6,7\}$ and $\{7,8,9\}$

1)  When two sets A and B are given, then the union, $A\cup B$ is the set of all the elements which are in A and B.

Therefore, $A\cup B=\{2,3,4,5,6,7\}\cup \{7,8,9\}$

$=\{2,3,4,5,6,7,8,9\}$

And $n(A\cup B)$  refers to the number of elements in the set $A\cup B$.

There are totally eight elements in the set, therefore,  $n(A\cup B)=8$.

2) When two sets A and B are given, then the intersection, $A\cap B$ is the set of all elements which are common in A and B.

Therefore, $A\cap B=\{2,3,4,5,6,7\}\cap \{7,8,9\}$

$=\{7\}$

And $n(A\cap B)$  refers to the number of elements in the set $A\cap B$.

There is only one element in the set, therefore,  $n(A\cap B)=1$.

Hence,$n(A\cup B)=8$ and $n(A\cap B)=1$.