Does a homogenous system always have multiple solutions?

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A homogeneous system Ax = 0 can have infinitely many solutions, but this does not imply that the non-homogeneous system Ax = b will also have infinitely many solutions. The non-homogeneous system can have one solution, no solutions, or infinitely many solutions depending on the vector b. The key point is that while Ax = 0 guarantees infinite solutions, Ax = b may not, leading to the conclusion that it may have either one solution or no solution. Therefore, the correct answer to the assignment question is that Ax = b must have either one solution or no solution.
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If a homogenous system Ax = 0 has infinitely many solutions, then for a non-zero vector b, the associated system Ax = b ____ have _______In my assignment, the answer I wrote on this question is must have many solutions. However, what I got is wrong.

Can anybody tell me why it is wrong?
 
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If Ax=0 gives infinite solutions and Ax=b => Ax≠ 0, why do you think it would give the same infinite number of solutions?
 
rock.freak667 said:
If Ax=0 gives infinite solutions and Ax=b => Ax≠ 0, why do you think it would give the same infinite number of solutions?

Well I am assuming there has to be many solutions since Ax=0 gives infinite solutions.

Plus, no solution or/and one solution sounds less appropriate than many solutions at the moment I answer the question.
 
rock.freak667 said:
If Ax=0 gives infinite solutions and Ax=b => Ax≠ 0, why do you think it would give the same infinite number of solutions?

Teacher gave me these choices:

A. may have exactly one solution
B. must have many solutions
C. must have either one solution or no solution
D. may have no solution
E. need not satisfy any of the above
 
shiri said:
Teacher gave me these choices:

A. may have exactly one solution
B. must have many solutions
C. must have either one solution or no solution
D. may have no solution
E. need not satisfy any of the above

For a system of equations written in the form Ax=b, you can have one solution, no solutions or infinite solutions.

You know for Ax=0 you have infinite solutions.

So for Ax≠ 0 would you still have infinite solutions?
 
rock.freak667 said:
For a system of equations written in the form Ax=b, you can have one solution, no solutions or infinite solutions.

You know for Ax=0 you have infinite solutions.

So for Ax≠ 0 would you still have infinite solutions?

I guess no. May have no solutions

Am I right?
 
shiri said:
I guess no. May have no solutions

Am I right?

or you can have one solution as well
 
rock.freak667 said:
or you can have one solution as well

one solution?

So it's C? must have either one solution or no solution?

why is that? Just curious
 
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