Giải phương trình:a) x(x-1) –(x+1)(x-2) =2b) (3x-2)(x2+1)=3x-2

* Hướng dẫn giải

a) x(x-1) –(x+1)(x-2) =2 <=>x²-x-(x²-2x+x-2)=2

                                        <=>x²-x-x²+x+2=2

                                        <=>2=2

  Vậy S=R

b) (3x-2)(x²+1)=3x-2 <=> (3x-2)(x²+1)-(3x-2)=0

                                    <=> (3x-2)(x²+1-1)=0

                                    <=> x²(3x-2)=0

                                    <=> 3x-2=0

                                    <=> x=\(\frac{2}{3}\)

  Vậy S={\(\frac{2}{3}\)}