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Question
Select the correct option from the given alternatives:
If `bar"a", bar"b", bar"c"` are non-coplanar unit vectors such that `bar"a"xx (bar"b"xxbar"c") = (bar"b"+bar"c")/sqrt2`, then the angle between `bar"a" "and" bar"b"` is
Options
`(3pi)/4`
`pi/4`
`pi/2`
`pi`
Solution
`(3pi)/4`
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