A. | B. |
C. | D. |
A.a =" (" 4, 2, 1 ), b =" (–1," 2 , 2 ), c =" (" –1, 1 ; 5 ). |
B. a =" (" 1, 2, –3 ), b =" (–2," –4 , 6 ) , c =" (" 1, 0 ,5 ). |
C.a =" (" 0, 0, 1 ), b =" (–1," 0 , 0 ), c =" (" 0, –1 ; 0 ). |
D.a =" (" –2, 3, 1 ), b =" (3," –2 , –2 ), c =" (" –1, 0 ; 2 ). |
A. | B. | C. | D. |
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