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Question
Choose the correct alternative:
The unit vector parallel to the resultant of the vectors `hat"i" + hat"j" - hat"k"` and `hat"i" - 2hat"j" + hat"k"` is
Options
`(hat"i" - hat"j" + hat"k")/sqrt(5)`
`(2hat"i" + hat"j")/sqrt(5)`
`(2hat"i" - hat"j" + hat"k")/sqrt(5)`
`(2hat"i" - hat"j")/sqrt(5)`
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Solution
`(2hat"i" - hat"j")/sqrt(5)`
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