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tballs
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I am having problems with this questions my physics teacher gave us. Since he doesn't explain things well, I do not know how he got an answer of 66. Can you please explain to me how to get this answer? THX.
For the following three vectors, what is C*(A X 3B) (the "*" is suppose to be a dot)
A = 4I -3J -2K B = -3I +1J +2K C = -3I + 5J -4K
I J K I J
4 -3 -2 4 -3
-9 3 6 -9 3
(18I+6I) + (18J-24J) + (-27K-12K)
24I - 6J - 39K
(24I X -3I) + (-6J X 5J) + (-39K X -4K)
-72I -30J +156
156-102
54
For the following three vectors, what is C*(A X 3B) (the "*" is suppose to be a dot)
A = 4I -3J -2K B = -3I +1J +2K C = -3I + 5J -4K
Homework Equations
I J K I J
4 -3 -2 4 -3
-9 3 6 -9 3
(18I+6I) + (18J-24J) + (-27K-12K)
24I - 6J - 39K
(24I X -3I) + (-6J X 5J) + (-39K X -4K)
-72I -30J +156
156-102
54