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If

 

then which one of the following is a value of x?

This question was previously asked in
NDA-I (Mathematics) Official Paper (Held On: 13 Apr, 2025)
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  1. -2
  2. -1
  3. 0
  4. 1

Answer (Detailed Solution Below)

Option 4 : 1
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Detailed Solution

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Calculation:

Multiply Matrix 1 and Matrix 2:

 

⇒

Multiply the resulting matrix with Matrix 3:

⇒

⇒

Equate the result to 45:

⇒

 

 

⇒

Step 5: Verify:

For , substitute back:

45 =45

∴ The correct value of x is 1.

Hence, the correct answer is Option 4.

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