alleryThe vector triple product a × (b × c) simplifies via:
A$a · (b × c)$ (the scalar triple)
B$(a × b) × c$ (always associative)
C$(a · c) b − (a · b) c$ (BAC − CAB)
D$|a||b||c| \sin \theta$ (single trig)
Answer & Solution
Correct answer: C. $(a · c) b − (a · b) c$ (BAC − CAB)
BAC − CAB rule: a × (b × c) = (a · c) b − (a · b) c.
The result lies in the plane of b and c.
Cross product is NOT associative.
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