解一元二次方程:(1)(2x-3)2=(a-2)(3a-4) (2)(x2-2x-2)2-7(x2-2x-2)+6=0
2个回答

(1)(2x-3)2=(a-2)(3a-4)

4x-6=3a^2-10a+8

4x=3a^2-10a+14

x=(3a^2-10a+14)/4

(2)(x2-2x-2)2-7(x2-2x-2)+6=0

[(x^2-2x-2)-6][(x^2-2x-2)-1]=0

(x^2-2x-8)(x^2-2x-3)=0

(x-4)(x+2)(x-3)(x+1)=0

x=4,x=-2,x=3,x=-1

(3) x2+5x+k2=2kx+5k+6

x^2+x(5-2k)+k^2-5k-6=0

x^2+x(5-2k)+(k-6)(k+1)=0

[x-(k-6)][x-(k+1)]=0

x=k-6,x=k+1

(4)x2-4ax+3a2=1-2a

x^2-4ax+3a^2+2a-1=0

x^2-4ax+(3a-1)(a+1)=0

[x-(3a-1)][x-(a+1)]=0

x=3a-1,x=a+1