Solving x1 and x2 with 4 & 5 Equations

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Homework Help Overview

The discussion revolves around solving a system of equations involving the derivatives of two variables, x1 and x2, presented in a set of linear equations. The equations include terms for the derivatives of x1 and x2 with respect to time, and participants are exploring methods to express these derivatives in terms of x1 and x2.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the possibility of expressing the derivatives dx1/dt and dx2/dt in terms of the variables x1 and x2. There is an attempt to introduce a substitution to simplify the equations, but some participants express confusion regarding the proposed methods.

Discussion Status

The discussion is ongoing, with some participants providing guidance on how to approach the problem by suggesting specific substitutions and forms for the derivatives. However, there is also a noted lack of understanding from some participants, indicating that clarification and further exploration of the problem are needed.

Contextual Notes

Participants are reminded of the forum rules, which require them to demonstrate some effort in solving the problem independently before receiving further assistance.

goodname
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can we solve x1 and x2 using the below quations? if so how?

4(dx1/dt)+5(x1)-2(dx2/dt)=10

-2(dx1/dt)+5(x2)-4(dx2/dt)=0
 
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Start by solving for dx1/dt and dx2/dt in terms of x1 and x2. Then use the substitution u(t) = x(t)-2 to get rid of the constant terms. You should end up with

\begin{pmatrix}\dot{u}(t) \\ \dot{x}_2(t)\end{pmatrix} = \begin{pmatrix} -1 & 1/2 \\ 1/2 & 1 \end{pmatrix}\begin{pmatrix} u(t) \\ x_2(t) \end{pmatrix}

You can solve that system using the usual methods.
 
sorry, i cannot understand..
 
Well, as per the forum rules, you need to show some effort at trying to solve the problem on your own. Start by solving for dx1/dt and dx2/dt in terms of x1 and x2. In other words, find the constants a, b, c, d, e, and f such that

\begin{align*}<br /> \frac{dx_1}{dt} &amp;= a x_1 + b x_2 + e \\<br /> \frac{dx_2}{dt} &amp;= c x_1 + d x_2 + f<br /> \end{align*}
 

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