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What is equal to?

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Answer (Detailed Solution Below)

Option 3 :
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Detailed Solution

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Concept:

  •  and  are two vectors parallel to each other ⇔  
  • Cross product of parallel vectors are zero ⇔  
  • A cross or vector product is not commutative ⇔ 


Calculation:

We have to find the value of 

We know that 

                 

∴ Option 3 is correct.

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