用配方法使下面等式成立:
(1)x2-2x-3=(x-______)2-_______;
(2)x2+0.4x+0.5=(x+_______)2+________;
(3)3x2+2x-2=3(x+______)2+________;
(4)x2+
x-2=
(x+________)2+_______.
用配方法使下面等式成立:
(1)x2-2x-3=(x-______)2-_______;
(2)x2+0.4x+0.5=(x+_______)2+________;
(3)3x2+2x-2=3(x+______)2+________;
(4)x2+
x-2=
(x+________)2+_______.