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Question
The value of `hati . (hatj xx hatk) + hatj . (hatk xx hati) + hatk . (hati xx hatj)` is ______
Options
0
–1
1
3
Solution
The value of `hati . (hatj xx hatk) + hatj . (hatk xx hati) + hatk . (hati xx hatj)` is 3.
Explanation:
`hati . (hatj xx hatk) + hatj . (hatk xx hati) + hatk . (hati xx hatj)`
= `hati . (hati) + hatj . (hatj) + hatk . (hatk)`
= 1 + 1 + 1
= 3
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