A little help

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algebrapro18

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Gift donations will be made to anyone who can help me with any of these:

A) For each part, find a function f: R -> R that has the desired properties: neither onto nor one-to-one

B)Under what conditions does A\\(A\\B) = B?

C)Define f:J -> N(natural numbers) where f(n) = 2n-1 for each n element of N(natural numbers).

D) Given A = {1,2,3,4,5}, B = {2,3,4,5,6,7} and C = {a,b,c,d,e} state an example of f: A ->B, g: B-> C, such that g(f(x))(the composition of g onto f) is 1-1 but g is not 1-1.

These are problems for homework that is due on Friday.
 
fastnoc

fastnoc

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Do you see the irony here in your username and this question?
 
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algebrapro18

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This isn't algebra, its graph theory, but yes I do see a little irony here. IF you need definitions of onto and 1-1(one-to-one) I will be happy to provide them.
 
fastnoc

fastnoc

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Oh i'm so far out of my league here it's scary
. I just thought it was funny.
 
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yosemite

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You aren't seriously asking for help are you? I thought you were just trying to show us how stupid we are in relation to your smarts.
 
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junior_j

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If im honest when i looked at that first time i thought u were asking the fuctions of key board computer keys lol ... i am kinda dumb aye lol
Jess x?
 
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algebrapro18

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Originally Posted by Yosemite

You aren't seriously asking for help are you? I thought you were just trying to show us how stupid we are in relation to your smarts.
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No I am very serious, I just can't figure those out. Its kind of funny because I was able to figure out the "harder" problems the teacher asked us.
 
mrblanche

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I once took an aptitude test, and the tester said, "Mr. Blanche, you have the largest vocabulary of anyone we've ever tested, but we suggest that if you ever get a job where you have to handle numbers, you get a secretary."

I got decent grades in Math (and a good SAT score), but I never gave them a second chance to question me about it!
 
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algebrapro18

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Originally Posted by algebrapro18

Gift donations will be made to anyone who can help me with any of these:

A) For each part, find a function f: R -> R that has the desired properties: neither onto nor one-to-one

B)Under what conditions does A\\(A\\B) = B?

C)Define f:J -> N(natural numbers) where f(n) = 2n-1 for each n element of N(natural numbers).

D) Given A = {1,2,3,4,5}, B = {2,3,4,5,6,7} and C = {a,b,c,d,e} state an example of f: A ->B, g: B-> C, such that g(f(x))(the composition of g onto f) is 1-1 but g is not 1-1.

These are problems for homework that is due on Friday.
Click to expand...
I got A, B, and D done so if anyone can help me with c then this will be done. IF anyone wants to see the solutions to A,B, and D I can also post them(I have a lot of free time today).
 
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Omg I cant believe you guys donâ€[emoji]8482[/emoji]t know this... Itâ€[emoji]8482[/emoji]s obvious the answer to all questions is 2!

Lol jk, who knows this stuff unless you are studying it?
 
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butzie

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Originally Posted by algebrapro18

I got A, B, and D done so if anyone can help me with c then this will be done. IF anyone wants to see the solutions to A,B, and D I can also post them(I have a lot of free time today).
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for B

"Under what conditions..."

A=1
B is not zero

If I'm right too, do I still get a prize?

f(n)=2n-1 is the set of odd numbers. Positive and negative. 0 is not a natural number
 
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butzie

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Originally Posted by butzie

for B

"Under what conditions..."

A=1
B is not zero

If I'm right too, do I still get a prize?

f(n)=2n-1 is the set of odd numbers. Positive and negative. 0 is not a natural number
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The last was the answer to C.

Now,that is worth 2 gifts.
 
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belongstoevie

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Originally Posted by mrblanche

And here I thought the answer to all of them was "42."
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That is, after all, the answer to, among others things, everything!
 
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butzie

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Originally Posted by butzie

The last was the answer to C.

Now,that is worth 2 gifts.
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Hey! Algebrapro18! I solved 2 of the 4, including the one that you did not know. So, where is my gift? We are all curious here.
 
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