Question

Which following relation is NOT a function?

Answer 1

the last one

Answer 2

ok can u tell me why

Answer 3

yes, what this really means is "is y a function of x"

Answer 4

..becasue it doesnt fit the definition of a function :)

Answer 5

So what is the definition smart one

Answer 6

something that should be known in order to answer the questions id assume ;)

Answer 7

so what happens if you solve for y? you get
\[y^2=x^2-4\]
\[y=\pm\sqrt{x^2-4}\]
and it is the plus or minus that throws you off

Answer 8

if you try to solve this with a table; the points that you come up with will not be "unique" enough

Answer 9

Thanks you satellite :-)

Answer 10

they will give you 2 results for every entery

Answer 11

so for example if x = 5 then y could be 1 or -1

Answer 12

Do you think you can help me with a couple more?

Answer 13

hello amstre! i have been busy all day

Answer 14

ive been doing homework for the first part, now i got time to just be bored

Answer 15

@jessica post away!

Answer 16

thanks!