( ewcommand{vecs}[1]{overset { scriptstyle rightharpoonup} {mathbf{#1}}})
( ewcommand{vecd}[1]{overset{-!-!rightharpoonup}{vphantom{a}smash{#1}}} )
( ewcommand{id}{mathrm{id}}) ( ewcommand{Span}{mathrm{span}})
( ewcommand{kernel}{mathrm{null},}) ( ewcommand{range}{mathrm{range},})
( ewcommand{RealPart}{mathrm{Re}}) ( ewcommand{ImaginaryPart}{mathrm{Im}})
( ewcommand{Argument}{mathrm{Arg}}) ( ewcommand{orm}[1]{| #1 |})
( ewcommand{inner}[2]{langle #1, #2 rangle})
( ewcommand{Span}{mathrm{span}})
( ewcommand{id}{mathrm{id}})
( ewcommand{Span}{mathrm{span}})
( ewcommand{kernel}{mathrm{null},})
( ewcommand{range}{mathrm{range},})
( ewcommand{RealPart}{mathrm{Re}})
( ewcommand{ImaginaryPart}{mathrm{Im}})
( ewcommand{Argument}{mathrm{Arg}})
( ewcommand{orm}[1]{| #1 |})
( ewcommand{inner}[2]{langle #1, #2 rangle})
( ewcommand{Span}{mathrm{span}}) ( ewcommand{AA}{unicode[.8,0]{x212B}})
( ewcommand{vectorA}[1]{vec{#1}} % arrow)
( ewcommand{vectorAt}[1]{vec{text{#1}}} % arrow)
( ewcommand{vectorB}[1]{overset { scriptstyle rightharpoonup} {mathbf{#1}}})
( ewcommand{vectorC}[1]{textbf{#1}})
( ewcommand{vectorD}[1]{overrightarrow{#1}})
( ewcommand{vectorDt}[1]{overrightarrow{text{#1}}})
( ewcommand{vectE}[1]{overset{-!