Find A ∩ B if A = {2, 5, 8, 11, 14} and B = {1, 3, 5, 7}.

Question

kinggeorge · Answer

Do you have a guess as to what the answer is?

mathteacher1729 · Answer

Do you understand what the symbol $\cap$ means?

anonymous · Answer

What does it mean A intersect B?

anonymous · Answer

no

anonymous · Answer

a crosses over b

mathteacher1729 · Answer

@tylertriebs the symbol $\cap $ means "All numbers which are in BOTH set A and set B.

anonymous · Answer

What number is the same in both A and B

mathteacher1729 · Answer

In other words, which numbers do the two sets have in common?

anonymous · Answer

7

anonymous · Answer

A = {2, 5, 8, 11, 14}  
IS there a 7 there?

mathteacher1729 · Answer

Look closely, is 7 in BOTH A and B?

anonymous · Answer

no whoops

anonymous · Answer

5

anonymous · Answer

Guess again?

anonymous · Answer

yeah u are right!!

anonymous · Answer

Keep looking for more numbers that are in both

anonymous · Answer

so is that the finall answer

mathteacher1729 · Answer

@tylertriebs you got it! :D Only 5 is in both sets.  So the answer should be written: 

$$\huge A \cap B =\{5\}$$

anonymous · Answer

ok  sweet

anonymous · Answer

so is it wrong if i put just {5}

mathteacher1729 · Answer

I would write the whole thing out like I did above.  It reads more like a complete sentence. 

"the intersection of A and B is the set containing just the number five." 

(This is why math is nice, you can write that entire sentence in just a few symbols!)

anonymous · Answer

ok ididnt know that thank you