Tìm x `(-x-1)^2 -3x+3=0`

1 bình luận về “Tìm x `(-x-1)^2 -3x+3=0`”

1. ????????????????????????????????????????????????????

   $\bullet$  (-x-1)^2-3x+3=0

   <=> x^2+2x+1-3x+3=0

   <=> x^2+(2x-3x)+(1+3)=0

   <=> x^2-x+4=0

   <=> x^2-2.x . 1/2+(1/2)^2-(1/2)^2+4=0

   <=> (x-1/2)^2+15/4=0

   <=> (x-1/2)^2=-15/4

   => Vô lí vì (x-1/2)^2>=0 ∀x

   Vậy x ∈ ∅

    

   Trả lời