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NDA2021MathematicsComplex NumberActual

Which one of the following is a square root of 2 a+2 a^2+b^2 , where a, b R ? where i= .

Options

  1. Aa+i b + a-i b
  2. Ba+i b - a-i b
  3. C2 a+i b
  4. D2 a-i b

Correct answer

A. a+i b + a-i b

Step-by-step solution

aligned & 2 a+2 a^2+b^2 =(a+i b)+(a-i b)+2 a^2-i^2 b^2 & =( a+i b )^2+( a-i b )^2+2 a+i b a-i b & =( a+i b + a-i b )^2 & Square root = ( a+i b + a-i b ) aligned

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