Răspuns :
[tex](x+1)(x-3)=x^2-3x+x-3=x^2-2x-3
(x-1)^2=(x+1)(x-2)=x^2+2x+1=x^2-2x+x-2
unde 2x+1=-2x+x-2
2x+1=-x-2
2x+x=-2-1 unde 3x=-3 deci x=-1[/tex]
(x-1)² = (x+1) (x-2)
[tex]\it (x-1)^2 = (x+1)(x-2) \Leftrightarrow x^2-2x+1= x^2-2x+x-2 \Leftrightarrow \\\;\\ \Leftrightarrow 1 = x-2 \Leftrightarrow 1+2=x \Leftrightarrow x=3[/tex]
[tex]\it (x-1)^2 = (x+1)(x-2) \Leftrightarrow x^2-2x+1= x^2-2x+x-2 \Leftrightarrow \\\;\\ \Leftrightarrow 1 = x-2 \Leftrightarrow 1+2=x \Leftrightarrow x=3[/tex]
