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What is the value of 2+ 1 2+ 1 2+ 1 2+

Options

  1. A2 -1
  2. B2 +1
  3. C3
  4. D4

Correct answer

B. 2 +1

Step-by-step solution

Let y=2+ 1 2+ 1 2+ aligned & y=2+ 1 y & y^2=2 y+1 & y^2-2 y-1=0 & y= 2 (-2)^2-4(-1) 2 & y= 2 2 2 2 =1 2 & y 2 & y=1 2 aligned

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