# Thread: Math problem...need a little help

1. ## Math problem...need a little help

OK well here is the question:

Give to examples of sets which can be put in a one to one correspondence with the following sets:
a. {a , e, i, o, u}

b. {5, 10, 15, ...}
2, 4, 6,...
7, 14, 21....

BUT I dont get part A

Anybody wanna take a shot... I have noooo clue ..

2. In mathematics, one-to-one correspondence refers to a situation in which the members of one set (call it A) can be evenly matched with the members of a second set (call it B). Evenly matched means that each member of A is paired with one and only one member of B, each member of B is paired with one and only one member of A, and none of the members from either set are left unpaired. The result is that every member of A is paired with exactly one member of B, and every member of B is paired with exactly one member of A. In terms of ordered pairs (a,b), where a is a member of A and b is a member of B, no two ordered pairs created by this matching process have the same first element and no two have the same second element. When this type of matching can be shown to exist, mathematicians say that "a one-to-one correspondence exists between the sets A and B."
That help at all? My only knowledge of one-to-one is from matrices, but this looks a bit different.

3. Originally Posted by Cheekz185
OK well here is the question:

Give to examples of sets which can be put in a one to one correspondence with the following sets:
a. {a , e, i, o, u}

b. {5, 10, 15, ...}
2, 4, 6,...
7, 14, 21....

BUT I dont get part A

Anybody wanna take a shot... I have noooo clue ..
set b is multiples of 5
the first set of answers is multples of 2.
the second set is multiples of 7.

but her'e the rub, if you add the first set of answers to set b, you get the second set of answers. lol tha'ts me over thinking though.
My best guess is that they're multiples. I think a,e,i, o,u...Are you sure its just not a bunch of variables? I mean, it says the FOLLOWING SETS, not each set. i think you have to treat them together. They must be variables

4. whats this for then Steve?

5. Wierd questions. What's the context? What level maths is this supposed to be? Any 5-element set could be put in 1-1 correspondence with a,e,i,o,u

6. couldnt that be any set of non vowels in acending order at the same interval?

bfjpv

7. If this is actually a maths question, then it has nothing to do with the fact they're vowels, or letters in fact.

{a,e,i,o,u} can be put in one-to-one correspondance with {b,f,g,h,p}, or {elephants,apples,pigs,fords,bananas} or even {£,\$,%,^,&}.

saying two sets can be put in 1-1 correspondance is just saying, I can pair up every element from one set with an element in another set. And every element from one set has a unique pair in the other set.

b) is there to show you an example of 1-1 correspondence with infinite sets. So, sort-of counter-intuitively, {1,2,3,4,5,..} would be a correct answer, as it is in 1-1 correspondence with {5,10,15,20,25,...}.

8. Well, I am no mathamajician. Just trying to logic out a pattern from the example.

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•