( ewcommand{vecs}[1]{overset { scriptstyle ightharpoonup} {mathbf{#1}} } )
( ewcommand{vecd}[1]{overset{-!-! ightharpoonup}{vphantom{a}smash {#1}}} )
( ewcommand{id}{mathrm{id}}) ( ewcommand{Span}{mathrm{span}})
( ewcommand{kernel}{mathrm{null},}) ( ewcommand{ ange}{mathrm{range},})
( ewcommand{RealPart}{mathrm{Re}}) ( ewcommand{ImaginaryPart}{mathrm{Im}})
( ewcommand{Argument}{mathrm{Arg}}) ( ewcommand{ orm}[1]{| #1 |})
( ewcommand{inner}[2]{langle #1, #2 angle})
( ewcommand{Span}{mathrm{span}})
( ewcommand{id}{mathrm{id}})
( ewcommand{Span}{mathrm{span}})
( ewcommand{kernel}{mathrm{null},})
( ewcommand{ ange}{mathrm{range},})
( ewcommand{RealPart}{mathrm{Re}})
( ewcommand{ImaginaryPart}{mathrm{Im}})
( ewcommand{Argument}{mathrm{Arg}})
( ewcommand{ orm}[1]{| #1 |})
( ewcommand{inner}[2]{langle #1, #2 angle})
( ewcommand{Span}{mathrm{span}}) ( ewcommand{AA}{unicode[.8,0]{x212B}})
( ewcommand{vectorA}[1]{vec{#1}} % arrow)
( ewcommand{vectorAt}[1]{vec{ ext{#1}}} % arrow)
( ewcommand{vectorB}[1]{overset { scriptstyle ightharpoonup} {mathbf{#1}} } )
( ewcommand{vectorC}[1]{ extbf{#1}} )
( ewcommand{vectorD}[1]{overrightarrow{#1}} )
( ewcommand{vectorDt}[1]{overrightarrow{ ext{#1}}} )
( ewcommand{vectE}[1]{overset{-!-! ightharpoonup}{vphantom{a}smash{mathbf {#1}}}} )
( ewcommand{vecs}[1]{overset { scriptstyle ightharpoonup} {mathbf{#1}} } )
( ewcommand{vecd}[1]{overset{-!-! ightharpoonup}{vphantom{a}smash {#1}}} )
( ewcommand{avec}{mathbf a}) ( ewcommand{vec}{mathbf b}) ( ewcommand{cvec}{mathbf c}) ( ewcommand{dvec}{mathbf d}) ( ewcommand{dtil}{widetilde{mathbf d}}) ( ewcommand{evec}{mathbf e}) ( ewcommand{fvec}{mathbf f}) ( ewcommand{ vec}{mathbf n}) ( ewcommand{pvec}{mathbf p}) ( ewcommand{qvec}{mathbf q}) ( ewcommand{svec}{mathbf s}) ( ewcommand{ vec}{mathbf t}) ( ewcommand{uvec}{mathbf u}) ( ewcommand{vvec}{mathbf v}) ( ewcommand{wvec}{mathbf w}) ( ewcommand{xvec}{mathbf x}) ( ewcommand{yvec}{mathbf y}) ( ewcommand{zvec}{mathbf z}) ( ewcommand{ vec}{mathbf r}) ( ewcommand{mvec}{mathbf m}) ( ewcommand{zerovec}{mathbf 0}) ( ewcommand{onevec}{mathbf 1}) ( ewcommand{ eal}{mathbb R}) ( ewcommand{ wovec}[2]{left[egin{array}{r}#1 \ #2 end{array} ight]}) ( ewcommand{ctwovec}[2]{left[egin{array}{c}#1 \ #2 end{array} ight]}) ( ewcommand{ hreevec}[3]{left[egin{array}{r}#1 \ #2 \ #3 end{array} ight]}) ( ewcommand{cthreevec}[3]{left[egin{array}{c}#1 \ #2 \ #3 end{array} ight]}) ( ewcommand{fourvec}[4]{left[egin{array}{r}#1 \ #2 \ #3 \ #4 end{array} ight]}) ( ewcommand{cfourvec}[4]{left[egin{array}{c}#1 \ #2 \ #3 \ #4 end{array} ight]}) ( ewcommand{fivevec}[5]{left[egin{array}{r}#1 \ #2 \ #3 \ #4 \ #5 \ end{array} ight]}) ( ewcommand{cfivevec}[5]{left[egin{array}{c}#1 \ #2 \ #3 \ #4 \ #5 \ end{array} ight]}) ( ewcommand{mattwo}[4]{left[egin{array}{rr}#1 amp #2 \ #3 amp #4 \ end{array} ight]}) ( ewcommand{laspan}[1]{ ext{Span}{#1}}) ( ewcommand{cal}{cal B}) ( ewcommand{ccal}{cal C}) ( ewcommand{scal}{cal S}) ( ewcommand{wcal}{cal W}) ( ewcommand{ecal}{cal E}) ( ewcommand{coords}[2]{left{#1 ight}_{#2}}) ( ewcommand{gray}[1]{color{gray}{#1}}) ( ewcommand{lgray}[1]{color{lightgray}{#1}}) ( ewcommand{ ank}{operatorname{rank}}) ( ewcommand{ ow}{ ext{Row}}) ( ewcommand{col}{ ext{Col}}) ( enewcommand{ ow}{ ext{Row}}) ( ewcommand{ ul}{ ext{Nul}}) ( ewcommand{var}{ ext{Var}}) ( ewcommand{corr}{ ext{corr}}) ( ewcommand{len}[1]{left|#1 ight|}) ( ewcommand{bar}{overline{vec}}) ( ewcommand{hat}{widehat{vec}}) ( ewcommand{perp}{vec^perp}) ( ewcommand{xhat}{widehat{xvec}}) ( ewcommand{vhat}{widehat{vvec}}) ( ewcommand{uhat}{widehat{uvec}}) ( ewcommand{what}{widehat{wvec}}) ( ewcommand{Sighat}{widehat{Sigma}}) ( ewcommand{lt}{}) ( ewcommand{amp}{&}) (definecolor{fillinmathshade}{gray}{0.9})