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Let α G = i ˆ 3 + j ˆ and β G = i ˆ 2 – j ˆ + k ˆ 3 . If β G = 1 β G – 2 β G , where 1 β G is parallel to α G and 2 β G is perpendicular to α G , then 1 β G × 2 β G is equal to :

1. – i ˆ 3 + j ˆ 9 + k ˆ 5
2. 2 1 (– i ˆ 3 + j ˆ 9 + k ˆ 5 )
3. i ˆ 3 – j ˆ 9 – k ˆ 5
4. 2 1 ( i ˆ 3 – j ˆ 9 + k ˆ 5 )

Correct answer: 2 1 (– i ˆ 3 + j ˆ 9 + k ˆ 5 )

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