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2.4.1: Ejercicios 2.4

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    En Ejercicios\(\PageIndex{1}\) —\(\PageIndex{6}\), una matriz\(A\) y vectores\(\vec{b}\),\(\vec{u}\) y\(\vec{v}\) se dan. Verificar eso\(\vec{u}\) y ambas\(\vec{v}\) son soluciones a la ecuación\(A\vec{x}=\vec{b}\); es decir, mostrar eso\(A\vec{u}=A\vec{v}=\vec{b}\).

    Ejercicio\(\PageIndex{1}\)

    \(A=\left[\begin{array}{cc}{1}&{-2}\\{-3}&{6}\end{array}\right],\)

    \(\vec{b}=\left[\begin{array}{c}{0}\\{0}\end{array}\right],\:\vec{u}=\left[\begin{array}{c}{2}\\{1}\end{array}\right],\:\vec{v}=\left[\begin{array}{c}{-10}\\{-5}\end{array}\right]\)

    Contestar

    \(A\vec{v}\)Multiplicar\(A\vec{u}\) y verificar.

    Ejercicio\(\PageIndex{2}\)

    \(A=\left[\begin{array}{cc}{1}&{-2}\\{-3}&{6}\end{array}\right],\)

    \(\vec{b}=\left[\begin{array}{c}{2}\\{-6}\end{array}\right],\:\vec{u}=\left[\begin{array}{c}{0}\\{-1}\end{array}\right],\:\vec{v}=\left[\begin{array}{c}{2}\\{0}\end{array}\right]\)

    Contestar

    \(A\vec{v}\)Multiplicar\(A\vec{u}\) y verificar.

    Ejercicio\(\PageIndex{3}\)

    \(A=\left[\begin{array}{cc}{1}&{0}\\{2}&{0}\end{array}\right],\)

    \(\vec{b}=\left[\begin{array}{c}{0}\\{0}\end{array}\right],\:\vec{u}=\left[\begin{array}{c}{0}\\{-1}\end{array}\right],\:\vec{v}=\left[\begin{array}{c}{0}\\{59}\end{array}\right]\)

    Contestar

    \(A\vec{v}\)Multiplicar\(A\vec{u}\) y verificar.

    Ejercicio\(\PageIndex{4}\)

    \(A=\left[\begin{array}{cc}{1}&{0}\\{2}&{0}\end{array}\right],\)

    \(\vec{b}=\left[\begin{array}{c}{-3}\\{-6}\end{array}\right],\:\vec{u}=\left[\begin{array}{c}{-3}\\{-1}\end{array}\right],\:\vec{v}=\left[\begin{array}{c}{-3}\\{59}\end{array}\right]\)

    Contestar

    \(A\vec{v}\)Multiplicar\(A\vec{u}\) y verificar.

    Ejercicio\(\PageIndex{5}\)

    \(A=\left[\begin{array}{cccc}{0}&{-3}&{-1}&{-3}\\{-4}&{2}&{-3}&{5}\end{array}\right],\)

    \(\vec{b}=\left[\begin{array}{c}{0}\\{0}\end{array}\right],\:\vec{u}=\left[\begin{array}{c}{11}\\{4}\\{-12}\\{0}\end{array}\right],\:\vec{v}=\left[\begin{array}{c}{9}\\{-12}\\{0}\\{12}\end{array}\right]\)

    Contestar

    \(A\vec{v}\)Multiplicar\(A\vec{u}\) y verificar.

    Ejercicio\(\PageIndex{6}\)

    \(A=\left[\begin{array}{cccc}{0}&{-3}&{-1}&{-3}\\{-4}&{2}&{-3}&{5}\end{array}\right],\)

    \(\vec{b}=\left[\begin{array}{c}{48}\\{36}\end{array}\right],\:\vec{u}=\left[\begin{array}{c}{-17}\\{-16}\\{0}\\{0}\end{array}\right],\:\vec{v}=\left[\begin{array}{c}{-8}\\{-28}\\{0}\\{12}\end{array}\right]\)

    Contestar

    \(A\vec{v}\)Multiplicar\(A\vec{u}\) y verificar.

    En Ejercicios\(\PageIndex{7}\) -\(\PageIndex{9}\), una matriz\(A\) y vectores\(\vec{b}\),\(\vec{u}\) y\(\vec{v}\) se dan. Verificar eso\(A\vec{u}=\vec{0}\),\(A\vec{v}=\vec{b}\) y\(A(\vec{u}+\vec{v})=\vec{b}\).

    Ejercicio\(\PageIndex{7}\)

    \(A=\left[\begin{array}{ccc}{2}&{-2}&{-1}\\{-1}&{1}&{-1}\\{-2}&{2}&{-1}\end{array}\right],\)

    \(\vec{b}=\left[\begin{array}{c}{1}\\{1}\\{1}\end{array}\right],\:\vec{u}=\left[\begin{array}{c}{1}\\{1}\\{0}\end{array}\right],\:\vec{v}=\left[\begin{array}{c}{1}\\{1}\\{-1}\end{array}\right]\)

    Contestar

    Multiplicar\(A\vec{u}\),\(A\vec{v}\) y\(A(\vec{u}+\vec{v})\) verificar.

    Ejercicio\(\PageIndex{8}\)

    \(A=\left[\begin{array}{ccc}{1}&{-1}&{3}\\{3}&{-3}&{-3}\\{-1}&{1}&{1}\end{array}\right],\)

    \(\vec{b}=\left[\begin{array}{c}{-1}\\{-3}\\{1}\end{array}\right],\:\vec{u}=\left[\begin{array}{c}{2}\\{2}\\{0}\end{array}\right],\:\vec{v}=\left[\begin{array}{c}{2}\\{3}\\{0}\end{array}\right]\)

    Contestar

    Multiplicar\(A\vec{u}\),\(A\vec{v}\) y\(A(\vec{u}+\vec{v})\) verificar.

    Ejercicio\(\PageIndex{9}\)

    \(A=\left[\begin{array}{ccc}{2}&{0}&{0}\\{0}&{1}&{-3}\\{3}&{1}&{-3}\end{array}\right],\)

    \(\vec{b}=\left[\begin{array}{c}{2}\\{-4}\\{-1}\end{array}\right],\:\vec{u}=\left[\begin{array}{c}{0}\\{6}\\{2}\end{array}\right],\:\vec{v}=\left[\begin{array}{c}{1}\\{-1}\\{1}\end{array}\right]\)

    Contestar

    Multiplicar\(A\vec{u}\),\(A\vec{v}\) y\(A(\vec{u}+\vec{v})\) verificar.

    En Ejercicios\(\PageIndex{10}\) -\(\PageIndex{24}\), se\(\vec{b}\) dan una matriz\(A\) y un vector.

    1. Resuelve la ecuación\(A\vec{x}=\vec{0}\).
    2. Resuelve la ecuación\(A\vec{x}=\vec{b}\).

    En cada uno de los anteriores, asegúrate de escribir tu respuesta en formato vectorial. También, cuando sea posible, dar 2 soluciones particulares a cada ecuación.

    Ejercicio\(\PageIndex{10}\)

    \(A=\left[\begin{array}{cc}{0}&{2}\\{-1}&{3}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{-2}\\{-1}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=\left[\begin{array}{c}{0}\\{0}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{-2}\\{-1}\end{array}\right]\)
    Ejercicio\(\PageIndex{11}\)

    \(A=\left[\begin{array}{cc}{-4}&{-1}\\{-3}&{-2}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{1}\\{4}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=\left[\begin{array}{c}{0}\\{0}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{2/5}\\{-13/5}\end{array}\right]\)
    Ejercicio\(\PageIndex{12}\)

    \(A=\left[\begin{array}{cc}{1}&{-2}\\{0}&{1}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{0}\\{-5}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=\left[\begin{array}{c}{0}\\{0}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{-10}\\{-5}\end{array}\right]\)
    Ejercicio\(\PageIndex{13}\)

    \(A=\left[\begin{array}{cc}{1}&{0}\\{5}&{-4}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{-2}\\{-1}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=\left[\begin{array}{c}{0}\\{0}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{-2}\\{-9/4}\end{array}\right]\)
    Ejercicio\(\PageIndex{14}\)

    \(A=\left[\begin{array}{cc}{2}&{-3}\\{-4}&{6}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{1}\\{-1}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{2}\left[\begin{array}{c}{3/2}\\{1}\end{array}\right]\)
    2. No hay solución.
    Ejercicio\(\PageIndex{15}\)

    \(A=\left[\begin{array}{ccc}{-4}&{3}&{2}\\{-4}&{5}&{0}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{-4}\\{-4}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{3}\left[\begin{array}{c}{5/4}\\{1}\\{1}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{1}\\{0}\\{0}\end{array}\right]+x_{3}\left[\begin{array}{c}{5/4}\\{1}\\{1}\end{array}\right]\)
    Ejercicio\(\PageIndex{16}\)

    \(A=\left[\begin{array}{ccc}{1}&{5}&{-2}\\{1}&{4}&{5}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{0}\\{1}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{3}\left[\begin{array}{c}{-33}\\{7}\\{1}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{5}\\{-1}\\{0}\end{array}\right]+x_{3}\left[\begin{array}{c}{-33}\\{7}\\{1}\end{array}\right]\)
    Ejercicio\(\PageIndex{17}\)

    \(A=\left[\begin{array}{ccc}{-1}&{-2}&{-2}\\{3}&{4}&{-2}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{-4}\\{-4}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{3}\left[\begin{array}{c}{14}\\{-10}\\{0}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{-4}\\{2}\end{array}\right]+x_{3}\left[\begin{array}{c}{14}\\{-10}\\{0}\end{array}\right]\)
    Ejercicio\(\PageIndex{18}\)

    \(A=\left[\begin{array}{ccc}{2}&{2}&{2}\\{5}&{5}&{-3}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{3}\\{-3}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{2}\left[\begin{array}{c}{-1}\\{1}\\{0}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{3/16}\\{0}\\{21/16}\end{array}\right]+x_{2}\left[\begin{array}{c}{-1}\\{1}\\{0}\end{array}\right]\)
    Ejercicio\(\PageIndex{19}\)

    \(A=\left[\begin{array}{cccc}{1}&{5}&{-4}&{-1}\\{1}&{0}&{-2}&{1}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{0}\\{-2}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{3}\left[\begin{array}{c}{2}\\{2/5}\\{1}\\{0}\end{array}\right]+x_{4}\left[\begin{array}{c}{-1}\\{2/5}\\{0}\\{1}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{-2}\\{2/5}\\{0}\\{0}\end{array}\right]+x_{3}\left[\begin{array}{c}{2}\\{2/5}\\{1}\\{0}\end{array}\right]+\left[\begin{array}{c}{-1}\\{2/5}\\{0}\\{1}\end{array}\right]\)
    Ejercicio\(\PageIndex{20}\)

    \(A=\left[\begin{array}{cccc}{-4}&{2}&{-5}&{4}\\{0}&{1}&{-1}&{5}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{-3}\\{-2}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{3}\left[\begin{array}{c}{-3/4}\\{1}\\{1}\\{0}\end{array}\right]+x_{4}\left[\begin{array}{c}{-3/2}\\{-5}\\{0}\\{1}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{-1/4}\\{-2}\\{0}\\{0}\end{array}\right]+x_{3}\left[\begin{array}{c}{-3/4}\\{1}\\{1}\\{0}\end{array}\right]+x_{4}\left[\begin{array}{c}{-3/2}\\{-5}\\{0}\\{1}\end{array}\right]\)
    Ejercicio\(\PageIndex{21}\)

    \(A=\left[\begin{array}{ccccc}{0}&{0}&{2}&{1}&{4}\\{-2}&{-1}&{-4}&{-1}&{5}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{3}\\{4}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{2}\left[\begin{array}{c}{-1/2}\\{1}\\{0}\\{0}\\{0}\end{array}\right]+x_{4}\left[\begin{array}{c}{1/2}\\{0}\\{-1/2}\\{1}\\{0}\end{array}\right]+x_{5}\left[\begin{array}{c}{13/2}\\{0}\\{-2}\\{0}\\{1}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{-5}\\{0}\\{3/2}\\{0}\\{0}\end{array}\right]+x_{2}\left[\begin{array}{c}{-1/2}\\{1}\\{0}\\{0}\\{0}\end{array}\right]+x_{4}\left[\begin{array}{c}{1/2}\\{0}\\{-1/2}\\{1}\\{0}\end{array}\right]+x_{5}\left[\begin{array}{c}{13/2}\\{0}\\{-2}\\{0}\\{1}\end{array}\right]\)
    Ejercicio\(\PageIndex{22}\)

    \(A=\left[\begin{array}{ccccc}{3}&{0}&{-2}&{-4}&{5}\\{2}&{3}&{2}&{0}&{2}\\{-5}&{0}&{4}&{0}&{5}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{-1}\\{-5}\\{4}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{4}\left[\begin{array}{c}{8}\\{-12}\\{10}\\{1}\\{0}\end{array}\right]+x_{5}\left[\begin{array}{c}{-15}\\{68/3}\\{-20}\\{0}\\{1}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{2}\\{-16/3}\\{7/2}\\{0}\\{0}\end{array}\right]+x_{4}\left[\begin{array}{c}{8}\\{-12}\\{10}\\{1}\\{0}\end{array}\right]+x_{5}\left[\begin{array}{c}{-15}\\{68/3}\\{-20}\\{0}\\{1}\end{array}\right]\)
    Ejercicio\(\PageIndex{23}\)

    \(A=\left[\begin{array}{ccccc}{-1}&{3}&{1}&{-3}&{4}\\{3}&{-3}&{-1}&{1}&{-4}\\{-2}&{3}&{-2}&{-3}&{1}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{1}\\{1}\\{-5}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{4}\left[\begin{array}{c}{1}\\{13/9}\\{-1/3}\\{1}\\{0}\end{array}\right]+x_{5}\left[\begin{array}{c}{0}\\{-1}\\{-1}\\{0}\\{1}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{1}\\{1/9}\\{5/3}\\{0}\\{0}\end{array}\right]+x_{4}\left[\begin{array}{c}{1}\\{13/9}\\{-1/3}\\{1}\\{0}\end{array}\right]+x_{5}\left[\begin{array}{c}{0}\\{-1}\\{-1}\\{0}\\{1}\end{array}\right]\)
    Ejercicio\(\PageIndex{24}\)

    \(A=\left[\begin{array}{ccccc}{-4}&{-2}&{-1}&{4}&{0}\\{5}&{-4}&{3}&{-1}&{1}\\{4}&{-5}&{3}&{1}&{-4}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{3}\\{2}\\{1}\end{array}\right]\)

    Contestar
    1. \(\vec{x}=x_{4}\left[\begin{array}{c}{3}\\{-1}\\{-6}\\{1}\\{0}\end{array}\right]+x_{5}\left[\begin{array}{c}{-17}\\{12}\\{44}\\{0}\\{1}\end{array}\right]\)
    2. \(\vec{x}=\left[\begin{array}{c}{7}\\{-6}\\{-19}\\{0}\\{0}\end{array}\right]+x_{4}\left[\begin{array}{c}{3}\\{-1}\\{-6}\\{1}\\{0}\end{array}\right]+x_{5}\left[\begin{array}{c}{-17}\\{12}\\{44}\\{0}\\{1}\end{array}\right]\)

    En Ejercicios\(\PageIndex{25}\) —\(\PageIndex{28}\), se\(\vec{b}\) dan una matriz\(A\) y un vector. Resuelve la ecuación\(A\vec{x}=\vec{b}\), escribe la solución en formato vectorial y dibuja la solución como la línea apropiada en el plano cartesiano.

    Ejercicio\(\PageIndex{25}\)

    \(A=\left[\begin{array}{cc}{2}&{4}\\{-1}&{-2}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{0}\\{0}\end{array}\right]\)

    Contestar

    \(\vec{x}=x_{2}\left[\begin{array}{c}{-2}\\{1}\end{array}\right]=x_{2}\vec{v}\)

    clipboard_e46b1e81e74ff69bc1efa2b1870096469.png

    Figura\(\PageIndex{1}\)

    Ejercicio\(\PageIndex{26}\)

    \(A=\left[\begin{array}{cc}{2}&{4}\\{-1}&{-2}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{-6}\\{3}\end{array}\right]\)

    Contestar

    \(\vec{x}=\left[\begin{array}{c}{-3}\\{0}\end{array}\right]+x_{2}\left[\begin{array}{c}{-2}\\{1}\end{array}\right]=\vec{x_{p}}+x_{2}\vec{v}\)

    clipboard_e7d4233acc2411f64fc8a317bbb81083d.png

    Figura\(\PageIndex{2}\)

    Ejercicio\(\PageIndex{27}\)

    \(A=\left[\begin{array}{cc}{2}&{-5}\\{-4}&{-10}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{1}\\{2}\end{array}\right]\)

    Contestar

    \(\vec{x}=\left[\begin{array}{c}{0.5}\\{0}\end{array}\right]+x_{2}\left[\begin{array}{c}{2.5}\\{1}\end{array}\right]=\vec{x_{p}}+x_{2}\vec{v}\)

    clipboard_ea192547b7ad69a2b0fd1db5a3a424ecd.png

    Figura\(\PageIndex{3}\)

    Ejercicio\(\PageIndex{28}\)

    \(A=\left[\begin{array}{cc}{2}&{-5}\\{-4}&{-10}\end{array}\right],\:\vec{b}=\left[\begin{array}{c}{0}\\{0}\end{array}\right]\)

    Contestar

    \(\vec{x}=x_{2}\left[\begin{array}{c}{2.5}\\{1}\end{array}\right]=x_{2}\vec{v}\)

    clipboard_e2f219edc40fad5b66c9b65f8d39bc499.png

    Figura\(\PageIndex{4}\)

    2.4.1: Ejercicios 2.4 is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.