Аналитическая геометрия и линейная алгебра. Умнов А.Е. - 88 стр.

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                                                   e→′ = e→ cosα + e→ sin α        →     →
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                                                              1
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                                                                         2
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                                                            x = x ′ cos α − y ′ sin α
                                                                                      
                                                            y = x ′ sin α + y ′ cos α
                                                 
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                  A( x ′ cos α − y ′ sin α ) 2 + 2 B( x ′ cos α − y ′ sin α )( x ′ sin α + y ′ cos α ) +
                                                                                                                                            
                  + C ( x ′ sin α + y ′ cos α ) 2 + 2 D( x ′ cos α − y ′ sin α ) + 2 E ( x ′ sin α + y ′ cos α ) + F = 0
              
              ÒãÒÎË A ′x ′ 2 + 2 B ′x ′y ′ + C ′y ′ 2 + 2 D ′x ′ + 2 E ′y ′ + F ′ = 0 
              
              |ˆ° ÈÓȲºÒ䈺
          
                                    A′ = A cos 2 α + 2 B cosα sin α + C sin 2 α
                                  2 B′ = −2 A sin α cosα + 2 B cos 2 α − 2 B sin 2 α + 2C sin α cosα 
                                   C ′ = A sin 2 α − 2 B cosα sin α + C cos 2 α.
          

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