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Question
Given that `veca.vecb = 0` and `veca xx vecb = 0` What can you conclude about the vectors `veca and vecb`?
Solution
It is given that `veca xx vecb = 0, veca xx vecb = 0`
`|veca| = 0; |vecb| = 0; veca ⊥ vecb`
`veca xx vecb = 0`
`|veca| = 0, |vecb| = 0; |veca||vecb|`
`veca xx vecb = 0`
Either `veca = vec0` or `vecb = vec0` ...[`veca ⊥ vecb "and" veca | |vecb` are not valid at the same time]
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