■サマーヴィルの等面四面体(その39)

 [r12,r13,r14]ex −[r11,r13,r14]ex

 [r22,r23,r24]   [r21,r23,r24]  

 [r32,r33,0 ]   [r31,r33,0 ]  

 [r11,r12,r14]ez −[r11,r12,r13]ew

 [r21,r22,r24]   [r21,r22,r23]  

 [r31,r32,0 ]   [r31,r32,r33]  

=−r32[r13,r14]+r33[r12,r14]ex

    [r23,r24]   [r22,r24]

 +r31[r13,r14]−r33[r11,r14]ey

    [r23,r24]   [r21,r24]

 −r31[r12,r14]+r32[r11,r14]ey

    [r22,r24]   [r21,r24]

 +r31[r12,r13]−r32[r11,r13]+r33[r11,r12]ew

    [r22,r23]   [r21,r23]   [r21,r22]  

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