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40.2: Under Defined Systems

  • Page ID
    70542
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    %matplotlib inline
    import numpy as np
    import matplotlib.pyplot as plt
    import sympy as sym
    sym.init_printing()

    An under-defined system is one that is non-invertible and the number of unknowns is more than the number of knowns. These system often have infinite numbers of possible solutions and solving them involves finding a set of simplified equations that represent all solutions.

    Often the simplest way to solve an under-defined systems of equations is to extract the solution directly from the reduced row echelon form.

    Question

    What is the reduced row echelon form of the matrix \(A= \left[\begin{matrix} 1 & 3 \\ 2 & 6 \end{matrix}\right]\).

    ##ADD example of solving an underdefined system.
    Question

    What are the solutions to the above systems of equations if \(b= \left[\begin{matrix} 10\\ 3 \end{matrix}\right]\)?

    #put your answer to the above quesiton here.

    This page titled 40.2: Under Defined Systems is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Dirk Colbry via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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