1)2-3x-2x²=-2(x+2)(x-1/2)=-(x+2)(2x-1)
2x²+3x-2=0
D=9+46=25
x1=(-3-5)/4=-2 U x2=(-3+5)/4=1/2
2x/(2x-1)-(x+1)/(x+2)+4/(x+2)(2x-1)=0
x≠1/2 U x≠-2
2x(x+2)-(x+1)(2x-1)+4=0
2x²+4x-2x²+x-2x+1+4=0
3x=-5
x=-5/3
6+7x-3x²=-3(x+2/3)(x-3)=-(3x+2)(x-3)
3x²-7x-6=0
D=49+42=121
x1=(7-11)/6=-2/3 U x2=(7+11)/6=3
(1-x)/(x-3)-2x/(3x+2)+4/(3x+2)(x-3)=0
x≠3 U x≠-2/3
(1-x)(3x+2)-2x(x-3)+4=0
3x+2-3x²-2x-2x²+6x+4=0
x²+7x+6=0
x1+x2=-7 U x1*x2=6
x1=-1 U x2=-6