Question

Please help me write a expression~
Write a rule so that for every input, the output is an even number!

Answer 1

Are the inputs from the set of integers?
If an input were, say 1/3, then two times 1/3 = 2/3 which is not even.

Answer 2

So would it be (nx2) ?

Answer 3

yup, nx2 or 2n is absolutely correct..

Answer 4

Thanks @hartnn :)

Answer 5

welcome :)

Answer 6

if you think about even function condition, f(-x)=f(x) then you will get the idea.

Answer 7

hmmm that makes sense. Thanks @LeeYeongKyu !

Answer 8

So would it be (nx2)
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The rule would be y = 2n where n is an integer.