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Question
If `veca.hati = veca.(hati + hatj) = veca.(hati + hatj + hatk)` = 1, then `veca` is ______.
Options
`hatk`
`hati`
`hatj`
`hati + hatj + hatk`
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Solution
If `veca.hati = veca.(hati + hatj) = veca.(hati + hatj + hatk)` = 1, then `veca` is `underlinebb(hati)`.
Explanation:
`hati.hati = hati.(hati + hatj)`
= `hati.(hati + hatj + hatk)`
1 = 1 + 0
= 1 + 0 + 0
= 1
Hence, a = `hati`.
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