Question 208676
Matrix  transformation,represents  a  technique that "maps  each point" into  something else.  Perhaps  a  rotation,  perhaps  a  reflection.
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This  is  accomplished  by  multiplying  the transformation  matrix,  by  the  matrix  of  the  initial  figure,
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if  the  initial  figure  is  a  triangle,  it  might  be  represented  by, (x1,y1), (x2,y2), and  (x3,y3).
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This  might  be  represented  by  the  matrix,  [ x1   x2  x3]
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,[ y1   y2  y3]
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To  rotate  the  triangle  90 degrees,
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[0  -1]  [ x1   x2   x3]  =  [x1   x2   x3]
[1   0]  [ y1   y2   y3]  =  [-y1 -y2  -y3]
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The general  form  for  rotation  is [ cos @   -sin@]
 ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,[ sin@    cos@ ]
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This  is  obviously  too  brief  a  review  of  a  very  powerful, but  complex  technique. Please  spend  a  few  minutes  with  a  good  text  to learn  the  finer details  of  the  technique.
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