- #1
Mathman23
- 254
- 0
Hi Guys,
I got this linear algebra question I hope You Guys can assist me with
Below there is a inhomogeneous system of linear equations which I solve:
[itex]x_{1} + 2x_{2} + x_{3} = a [/itex]
[itex]3x_{1} + 4x_{2} + 2x_{3} = a - 3 [/itex]
[itex]-4x_{1} + 2x_{2} + x_{3} = 3 [/itex]
I then end up the following matrix:
1 0 0 0 -3a/5
0 1 1/2 (2a+3)/5
0 0 0 (-11a/10)
I´m then supose to prove if its possible to solve the system for every a-value.
By solving the equation (2a+3)/5) = 0. I then get an a-value a = -1/2 .
If I insert this a into the above matrix and row-reduce that matrix I get:
1 0 0 0
0 1 1/2 0
0 0 0 1
I then do some tests and then conclude if I choose an a-value in the interval
[-1000000,1000000]. I still end up the same matrix above.
Is it then correct to assume if I chose an a-value in the interval [-infty,infty]. I would then still end up with the same matrix?
If my assumption is correct, is it then safe to assume that its possible to solve the system of linear-equations for every a-value??
sincerely
Fred
I got this linear algebra question I hope You Guys can assist me with
Below there is a inhomogeneous system of linear equations which I solve:
[itex]x_{1} + 2x_{2} + x_{3} = a [/itex]
[itex]3x_{1} + 4x_{2} + 2x_{3} = a - 3 [/itex]
[itex]-4x_{1} + 2x_{2} + x_{3} = 3 [/itex]
I then end up the following matrix:
1 0 0 0 -3a/5
0 1 1/2 (2a+3)/5
0 0 0 (-11a/10)
I´m then supose to prove if its possible to solve the system for every a-value.
By solving the equation (2a+3)/5) = 0. I then get an a-value a = -1/2 .
If I insert this a into the above matrix and row-reduce that matrix I get:
1 0 0 0
0 1 1/2 0
0 0 0 1
I then do some tests and then conclude if I choose an a-value in the interval
[-1000000,1000000]. I still end up the same matrix above.
Is it then correct to assume if I chose an a-value in the interval [-infty,infty]. I would then still end up with the same matrix?
If my assumption is correct, is it then safe to assume that its possible to solve the system of linear-equations for every a-value??
sincerely
Fred