Home › UP Board Class 12 › mathematics › Vector Algebra › Three vectors $\vec a, \vec b, \vec c$ are copla…
Three vectors $\vec a, \vec b, \vec c$ are coplanar if and only if:
A$\vec a + \vec b + \vec c = 0$ on the school chart here
B$\vec a\cdot\vec b = \vec b\cdot\vec c = 0$ on the chart all the time
C$|\vec a| + |\vec b| = |\vec c|$ on chart at all times
DTheir scalar triple product $[\vec a\, \vec b\, \vec c] = 0$
Answer & Solution
Correct answer: D. Their scalar triple product $[\vec a\, \vec b\, \vec c] = 0$
Three vectors are coplanar iff their scalar triple product (parallelepiped volume) is zero.
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