+01520]6(350 puo t-pwuc Ths Om P qul SOFk Ds SISmSLIOIL T NumL vSNFCs 10 ∑ a ndo m2 l s=1Is's=1×1MI×IMB×B=14 B puo t-I ot uue Ths (m Fk thS KCFAMOFk R p mhlumL vMFCos ILAE 1o ∑Xm=sE=Es (RSASCSLNS SSS(SSLS AKKSLAH A, P. 803-845MATRIX ALGEBRA 6 Sum of Squares The sum of squares of the elements in a column vector x is n i=1 x 2 i = x ′x Example 18 x =    1 2 3    , x ′x = 1 × 1 + 2 × 2 + 3 × 3 = 14 Sum of Products The sum of the products of two column vectors x and y is n i=1 xiyi = x ′y = y ′x (Reference: See Greene Appendix A, P. 803—845)