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If  is a vector such that its magnitude is  then find the value of x

  1. ± √7
  2. ± √2
  3. ± √5
  4. ± √3

Answer (Detailed Solution Below)

Option 3 : ± √5
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Detailed Solution

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CONCEPT:

If  is a vector then magnitude of  is given by: 

CALCULATION:

Given:  is a vector such that its magnitude is 

As we know that, if   then magnitude of  is given by: 

So, 

By squaring both the sides of the above equation we get,

⇒ 10 = 2 + 3 + x2

⇒ x2 = 5

⇒ x = ± √5

Hence, option C is the correct answer.

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Last updated on Jul 1, 2025

-> The Indian Army has released the Exam Date for Indian Army Havildar SAC (Surveyor Automated Cartographer).

->The Exam will be held on 9th July 2025.

-> Interested candidates had applied online from 13th March to 25th April 2025.

-> Candidates within the age of 25 years having specific education qualifications are eligible to apply for the exam.

-> The candidates must go through the Indian Army Havildar SAC Eligibility Criteria to know about the required qualification in detail. 

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