Recent content by beatka6

Thank you all, I got it now

No, the problem is that we did not go over anything, the teacher does not explain anything and I am trying to figure it out myself. From my previous class I know something about inverse function, but only enough to find an inverse of given function and to find out if it is one to one or onto...

Abstact math help, function proof! Homework Statement Let f : X to Y . For each element b element of Y , let Y_b = f^-1({b}). Prove that the Y_b's have the following property: (a) If b and c are distinct elements of Y , then Yb intersection Yc = ∅. (b) X =U_element of Y ( Yb). 1...

Homework Statement Let f: Z to ZxZ be the function defined f(t)=(3t, 3t+1) . Let B denote the subset of ZxZ defined by B={ (5m, 5m+1) : m is an element of Z}. Determine f^-1(B). This means that you should define set S with a property of S=f^-1(B). In addition, your definition of S should make...

So would the formula for negative be a_(n+1)=a_(n-1)+2(-n+1) and do we still you the same a0=4?

It s number 5 from the attachment.

Ok I got it know, so in my set I have to put that this is for positive integers and find one for negative integers??

but then a_2=4+2(2)=8, or I am still missing something, for n=1,

I see the pattern, so 2=2*1; 4=2*2; 6=2*(2+1)=2*3; 10=2*(3+2);16=2*(5+3)=2*8 ; so now how can I write that? Let a_0=1, a_1=2; then a_(n+1)=2(a_n+a_n-1) so then a_2=2(a_0+a_1)=6, but it does not work for a_3. I really have no idea how to write it

Homework Statement If A is a set that contains a finite number of elements, we say A is a finite set. If A is a finite set, we write |A| to denote the number of elements in the set A. We also write |B| < ∞ to indicate that B is a finite set. Denote the sets X and Y by X = {T : T is a proper...

Am I anywhere close to find an answer?

So should I use Fibonacci numbers to find this sequence?? I still can't figure it out. a_n=4,a_(n+1)=a_n+2;a_(n+2)=a_(n+1)+a_n where n is an integers and a_0=4 ?

And this would work only for negative integers so I'm still completely lost.

I still have to idea how to find a formula. I was thinking about that n(n+1)=-4 but I don't think it's right. I can't come out with anything else. Then S1={n is an integer; n(n+1)=-4}.

So can you help me with that??