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Question
The value of is `hati.(hatj xx hatk)+hatj.(hatixxhatk)+hatk.(hatixxhatj)` is ______.
Options
0
-1
1
3
Solution
The value of is `hati.(hatj xx hatk)+hatj.(hatixxhatk)+hatk.(hatixxhatj)` is 1.
Explanation:
`hati.(hatj xx hatk) + hatj.(hati xx hatk) + hatk.(hati xx hatj)`
= `hati.hati + hatj(-hatj) + hatk.hatk`
= `1 - hatj.hatj + 1`
= 1 - 1 + 1
= 1
The correct answer is 1.
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