Simple vector judgment The necessary and sufficient condition for vectors a and B to be collinear is that "there exists n ∈ R, B = n * a" The answer is incorrect. Why? (2008 Hainan, Ningxia, Wen 9 li 8)

If B is a non-zero vector and a is a zero vector, then we cannot deduce the existence of n ∈ R, B = n * a
Therefore, it is a necessary and insufficient condition

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