Solving Systems of Equations over F2

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Suy
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Homework Statement



Find all solutions to the system of equations with over the binary field F2
w+x +z=0
x+y =1
enter you answer as a list of point (w,x,y,z)

Homework Equations





The Attempt at a Solution


This question should be easy, but I just don't understand binary field F2,
I know 0+0=0 1+1=0 0+1=0
Also , i tried to put (0,0,1,1)
which is
0+0 +1=0
0+1 =1
but it said wrong, please help me!
 
on Phys.org
0+0+1=1, not 0.

You start with x+y=1. There are two possibilities: x=1 and y=0 or x=0 and y=1 (there are only four choices for x and y, and these are the only two that work). Solve for possible choices of w+x+z=0 for each case using similar logic
 
0+0+0=0
1+1+0=0
0+1+1=0
is that mean there are 9 choices?
if 0+1=1, 0+0+0=0?
answer is (0,0,1,0)?
or 1+0=1
(1,1,0,0)
(0,1,0,1)
there is three answer, which one is right?
btw, what exactly is F2? I tried to google, but there isn't any answer
ty
 
Last edited:
The only possible values in the binary field are 0 and 1. There are two possible values for x, two for y, and two for z so there are (2)(2)(2)= 8 possible values for x, y, and z:
0, 0, 0
0, 0, 1
0, 1, 0
0, 1, 1
1, 0, 0
1, 0, 1
1, 1, 0
1, 1, 1
0, 0, 1

Since your two equations have 4 unknowns, x, y, z, and w, there are 2(2)(2)(2)= 16 possible sets of values but you don't have to look explicitely at all 16.

Since x occurs in both equations, if x= 0, we have w+ z= 0 and y= 1. So we only have to solve w+ z= 0. There are 4 cases:
w= 0, z= 0. Then w+ z= 0+ 0= 0
w= 1, z= 0. Then w+ z= 1+ 0= 1
w= 0, z= 1. Then w+ z= 0+ 1= 1
w= 1, z= 1. Then w+ z= 1+ 1= 0.
Two solutions are x= 0, y= 1, z= 0, w= 0 and x= 0, y= 1, z= 1, w= 1.

If x= 1, then we have w+ 1+ z= 0 and 1+ y= 0. y= 1 is the same as y= "-1"= 1 and w+ 1+ z= 0 is the same as w+ z= "-1"= 1 ("-1" in this field is 1 because 1+ 1= 0).
w= 0, z= 1 and w= 1, z= 0 both give w+ z= 1 so we also have x=1, y= 1, z= 1, w= 0 and x= 1, y= 1, z= 0, w= 1 .

That gives a total of 4 distinct solutions.
 
Thx! I probably confused with 1+1=0 those stuff, but like u said there is four answer, does it matter which one I put?
 
Suy said:
Thx! I probably confused with 1+1=0 those stuff, but like u said there is four answer, does it matter which one I put?

Oh nvm, I put all four answer and it's correct
 
hey i would like to know what exactly you put for your answer
 
(x,x,x,x),(x,x,x,x)
you can click preview to see if the format is correct
 
Thanks that worked, are by any chance in math 211 using webwork
 
are you by any chance...***