1.6x=3-2x²
2x²+6x=3
x²+3x=3/2
(x+3/2)²=3/2+(3/2)²
(x+3/2)²=15/4
x+3/2=±(√15)/2
x=(-3±√15)/2
2.3(2x-1)²-4（2x-1)=4
3(4x²-4x+1)-8x+4=4
12x²-12x+38x=0
12x²+26x=0
x(6x+13)=0
x=0或x=-13/6
3.2（x-2)²+4-x²=0
2(x²-4x+4)+4-x²=0
2x²-8x+8+4-x²=0
x²-8x+12=0
(x-2)(x-6)=0
x=2或x=6