Is My Matrix Approach to Solving Linear Equations with Parameters Correct?

monsmatglad
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Homework Statement


hi. i have a linear equation with parameters that i am trying to solve. unknowns are x, y and z.
(12-3t)x + 2y +2z =2
x +0*y +2z =0
12x + (2-t)y + (2-t)z = 12

i am using a matrix-approach with Gaussian-elimination, and my results (for values of t which allows for a specific solution) seem reasonable, but the the variables depend on t. is this correct, or will the answers be without the parameter t even if t is not specified. i believe i have seen a similar problem in one of my books where the solution is without the parameter t.

Homework Equations


am i getting it wrong?

The Attempt at a Solution


x= -(2t+20)/(3t2t), y= -(37t-110)/(3t2t), z= (t+10)/(3t2t)
 
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I think you're doing just fine. For every value of t (*) you have a different set of equations, so it's no wonder t appears in the solution.

(*) for t=0 you get conflicting equations, so it's not surprising there is no answer for x,y,z.
 
I am puzzled as to why you are writing "t^2t" rather than "t^3". Am I misunderstanding what you mean?
 
monsmatglad said:

The Attempt at a Solution


x= -(2t+20)/(3t2t), y= -(37t-110)/(3t2t), z= (t+10)/(3t2t)
Check the denominator. I think you just copied it wrong.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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