How Do You Solve a System with Variables and Constants?

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JaZZyCooL
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Homework Statement


Solve the following system of equations

Homework Equations


A1 + A3 = 0
cA1 + A2 + A4 = 0
dA1 + cA2 + w^2 A3 = 1
dA2 + w^2A4 = 0

The Attempt at a Solution



https://imgur.com/YSG5oGN - Page 1
https://imgur.com/dGbccsE - Page 2
 
I checked with Mathematica. Your expressions for A2 and A4 are correct. Your expression for A3 is not.
 
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kuruman said:
I checked with Mathematica. Your expressions for A2 and A4 are correct. Your expression for A3 is not.
Knowing that, the OP should be able to easily fix A1 and A3.
 
scottdave said:
Knowing that, the OP should be able to easily fix A1 and A3.
I agree. This particular system lends itself to using Cramer's rule because of all the zeroes on the right hand side.
 
JaZZyCooL said:

Homework Statement


Solve the following system of equations

Homework Equations


A1 + A3 = 0
cA1 + A2 + A4 = 0
dA1 + cA2 + w^2 A3 = 1
dA2 + w^2A4 = 0

The Attempt at a Solution



https://imgur.com/YSG5oGN - Page 1
https://imgur.com/dGbccsE - Page 2
Here is your Page 1:
Handwritten working on lined paper: a system of linear equations in A1, A2, A3 with constants c, d, w, being rearranged and substituted, ending with A2 multiplied by a bracketed expression in d, w and c equal to c.


Here is your Page 2:
Handwritten algebra working solving for A1, A2 and A3 in terms of c, d and omega, with intermediate expressions and boxed final results.
 
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  • Handwritten working on lined paper: a system of linear equations in A1, A2, A3 with constants c, d, w, being rearranged and substituted, ending with A2 multiplied by a bracketed expression in d, w and c equal to c.
    YSG5oGN.jpg
    24.9 KB · Views: 393
  • Handwritten algebra working solving for A1, A2 and A3 in terms of c, d and omega, with intermediate expressions and boxed final results.
    dGbccsE.jpg
    27.3 KB · Views: 403
the system shows two nonlinear equations. Not linear system.
 
symbolipoint said:
the system shows two nonlinear equations. Not linear system.
The system is linear in A1, A2, A3, and A4 .
 
SammyS said:
The system is linear in A1, A2, A3, and A4 .
These two equations are shown in the system:
dA1 + cA2 + w^2 A3 = 1
dA2 + w^2A4 = 0
Not linear. That shows an exponent of 2 on the w. If I misunderstand, then w is not a variable; but A1, A2, and A3 must be the variables. If this latter is the case, then yes; linear system.