Click for printer friendely version of this HowTo . $${\bf C}\boldsymbol{\beta}{\bf U} = \left[ \begin{array}{ccccccc} 1 & 1 & 1 & -1 & -1 & -1 & 0 \end... ... \end{array} \right] \left[ \begin{array}{cc} 1 & 0 0 & 1 \end{array} \right]$$ $$= \left[ \begin{array}{cc} (\beta_{1,1} + \beta_{2,1} + \beta_{3,... ... \end{array} \right] \left[ \begin{array}{cc} 1 & 0 0 & 1 \end{array} \right]$$ $$= \left[ \begin{array}{c} (\beta_{1,1} + \beta_{2,1} + \beta_{3,1... ... + \beta_{3,2}) - (\beta_{4,2} + \beta_{5,2} + \beta_{6,2}) \end{array} \right]$$

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