Question 219584
if  we  review,,,(a+b)^2 = (a+b) * (a+b) = a^2 +2ab +b^2
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looking  at  coefficients, 2given / 2(half) =1,,,1^2 = 1(3rd  coefficient)
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therefore  if  we  have  2nd  coefficient,  take  half  and  square  it  to  get  3rd  coefficient.
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x^2 -3x + 2.25,,,,,,,-3/2=-1.5,,,,,-1.5^2 = 2.25
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check,,,,(x-1.5)^2 = (x-1.5)(x-1.5) = x^2 -1.5x -1.5x +2.25 = x^2 -3x +2.25
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note,,,1.5 = 3/2
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