Question

i think yes but im not forsure.
Does the following set of ordered pairs express the first variable as a function of the second variable? {(2, -4)(-2, 0)(2, 2)(-2, 4)(3, -2)(-3, -2)}

Answer 1

Hmm. For a variable 'a' to be a function of a second variable 'b', only one specific value of 'b' may exist for every 'a'.

In the given set of ordered pairs, the second variables are the 'a', and the first variables are the 'b'.

Now if you see carefully, there are pairs like (3,-2) and (-3,-2). That means two values of 'b', ('-3' and '3' in this case) for the same 'a' ('-2' in this case).

So what do you think about this? Function or not a function?

Answer 2

yes

Answer 3

Yes what? read up and say.

Answer 4

yes cause the a and b values for the pairs are the same

Answer 5

No they aren't same!! There are two 'b' values for the same 'a'!!

And this violates the definition of a function!

Answer 6

ohh they looked the same for some of the pairs..

Answer 7

yeah they may be, but we do not need that really. We need to see that their is a unique 'b' value for every 'a'. No 2 or mores values of 'b' for the same 'a'.

Answer 8

ohh okay i see now.. thanks

Answer 9

so, function or not?

Answer 10

not

Answer 11

It's a 'relation' all right, but not a function. that is second variables ---> first variables.



And yes, right, it is not. Good work :)

Answer 12

thank you :)