Reducerad radtrappstegsform för $$$\left[\begin{array}{cccc}- \sqrt{6} & 0 & 1 & 0\\0 & - \sqrt{6} & 1 & 0\\1 & 1 & - \sqrt{6} & 2\\0 & 0 & 2 & - \sqrt{6}\end{array}\right]$$$

Bestäm den reducerade radtrappstegsformen för $$$\left[\begin{array}{cccc}- \sqrt{6} & 0 & 1 & 0\\0 & - \sqrt{6} & 1 & 0\\1 & 1 & - \sqrt{6} & 2\\0 & 0 & 2 & - \sqrt{6}\end{array}\right]$$$.

Dividera rad $$$1$$$ med $$$- \sqrt{6}$$$: $$$R_{1} = - \frac{\sqrt{6}}{6} R_{1}$$$.

$$$\left[\begin{array}{cccc}1 & 0 & - \frac{\sqrt{6}}{6} & 0\\0 & - \sqrt{6} & 1 & 0\\1 & 1 & - \sqrt{6} & 2\\0 & 0 & 2 & - \sqrt{6}\end{array}\right]$$$

Subtrahera rad $$$1$$$ från rad $$$3$$$: $$$R_{3} = R_{3} - R_{1}$$$.

$$$\left[\begin{array}{cccc}1 & 0 & - \frac{\sqrt{6}}{6} & 0\\0 & - \sqrt{6} & 1 & 0\\0 & 1 & - \frac{5 \sqrt{6}}{6} & 2\\0 & 0 & 2 & - \sqrt{6}\end{array}\right]$$$

Dividera rad $$$2$$$ med $$$- \sqrt{6}$$$: $$$R_{2} = - \frac{\sqrt{6}}{6} R_{2}$$$.

$$$\left[\begin{array}{cccc}1 & 0 & - \frac{\sqrt{6}}{6} & 0\\0 & 1 & - \frac{\sqrt{6}}{6} & 0\\0 & 1 & - \frac{5 \sqrt{6}}{6} & 2\\0 & 0 & 2 & - \sqrt{6}\end{array}\right]$$$

Subtrahera rad $$$2$$$ från rad $$$3$$$: $$$R_{3} = R_{3} - R_{2}$$$.

$$$\left[\begin{array}{cccc}1 & 0 & - \frac{\sqrt{6}}{6} & 0\\0 & 1 & - \frac{\sqrt{6}}{6} & 0\\0 & 0 & - \frac{2 \sqrt{6}}{3} & 2\\0 & 0 & 2 & - \sqrt{6}\end{array}\right]$$$

Multiplicera rad $$$3$$$ med $$$- \frac{\sqrt{6}}{4}$$$: $$$R_{3} = - \frac{\sqrt{6}}{4} R_{3}$$$.

$$$\left[\begin{array}{cccc}1 & 0 & - \frac{\sqrt{6}}{6} & 0\\0 & 1 & - \frac{\sqrt{6}}{6} & 0\\0 & 0 & 1 & - \frac{\sqrt{6}}{2}\\0 & 0 & 2 & - \sqrt{6}\end{array}\right]$$$

Lägg till rad $$$3$$$ multiplicerad med $$$\frac{\sqrt{6}}{6}$$$ till rad $$$1$$$: $$$R_{1} = R_{1} + \frac{\sqrt{6}}{6} R_{3}$$$.

$$$\left[\begin{array}{cccc}1 & 0 & 0 & - \frac{1}{2}\\0 & 1 & - \frac{\sqrt{6}}{6} & 0\\0 & 0 & 1 & - \frac{\sqrt{6}}{2}\\0 & 0 & 2 & - \sqrt{6}\end{array}\right]$$$

Lägg till rad $$$3$$$ multiplicerad med $$$\frac{\sqrt{6}}{6}$$$ till rad $$$2$$$: $$$R_{2} = R_{2} + \frac{\sqrt{6}}{6} R_{3}$$$.

$$$\left[\begin{array}{cccc}1 & 0 & 0 & - \frac{1}{2}\\0 & 1 & 0 & - \frac{1}{2}\\0 & 0 & 1 & - \frac{\sqrt{6}}{2}\\0 & 0 & 2 & - \sqrt{6}\end{array}\right]$$$

Subtrahera rad $$$3$$$ multiplicerad med $$$2$$$ från rad $$$4$$$: $$$R_{4} = R_{4} - 2 R_{3}$$$.

$$$\left[\begin{array}{cccc}1 & 0 & 0 & - \frac{1}{2}\\0 & 1 & 0 & - \frac{1}{2}\\0 & 0 & 1 & - \frac{\sqrt{6}}{2}\\0 & 0 & 0 & 0\end{array}\right]$$$

Eftersom elementet i rad $$$4$$$ och kolumn $$$4$$$ (pivot-elementet) är lika med $$$0$$$, måste vi byta plats på raderna.

Hitta det första nollskilda elementet i kolumn $$$4$$$ under pivotelementet.

Som synes finns det inga sådana poster.

Den reducerade radtrappstegsformen är $$$\left[\begin{array}{cccc}1 & 0 & 0 & - \frac{1}{2}\\0 & 1 & 0 & - \frac{1}{2}\\0 & 0 & 1 & - \frac{\sqrt{6}}{2}\\0 & 0 & 0 & 0\end{array}\right]\approx \left[\begin{array}{cccc}1 & 0 & 0 & -0.5\\0 & 1 & 0 & -0.5\\0 & 0 & 1 & -1.224744871391589\\0 & 0 & 0 & 0\end{array}\right].$$$A