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If , then which of the following is/are correct? 

1. Vectors a and b are orthogonal

2.  ()

Select the correct answer using the code given below 

  1. Only 1
  2. Only 2
  3. Both 1 and 2
  4. Neither 1 nor 2

Answer (Detailed Solution Below)

Option 1 : Only 1
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Detailed Solution

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Concept:

If vectors a and b are orthogonal, then 

 

Calculation: 

Here, 

Squaring both sides we get, 

⇒4= 0

⇒= 0

So, Vectors a and b are orthogonal

As we know, if  then 

So, only (1) is correct.

Hence, option (1) is correct.

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