Is this a correct function?
- Thread starter Sophdof1
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Dr.Peterson
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Do you have a reason to think it might either be injective, or not be surjective?
It looks good to me.
It looks good to me.
They asked for a surjective function that isn’t injective. Are you sure I am correct?
I think I just have a loss of confidence that’s why I asked
Dr.Peterson
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The best way to become confident is to convince yourself that you are right by writing out your reasons.
So convince me: Why is it surjective? Why is it not injective? (You are correct, so you should be able to answer both questions.)
So convince me: Why is it surjective? Why is it not injective? (You are correct, so you should be able to answer both questions.)
pka
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Here is an interesting function: \(\displaystyle \phi (n) = \left\lfloor {\frac{{n + 1}}{2}} \right\rfloor \) [That is the floor function].
Steven G
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What does injective mean? Does your function satisfy the definition. Why?I think I just have a loss of confidence that’s why I asked
What does surjective mean? Does your function satisfy the definition. Why?