①(2x-1)(x+1)=(3x+1)(x+1)
(3x+1)(x+1)-(2x-1)(x+1)
=(3x+1-2x+1)(x+1)
=(x+2)(x+1)=0
x=-1,-2
②(2x+1)^2+3(2x+1)+2=0
((2x+1)+1)((2x+1)+2)=0
2(x+1)(2x+3)=0
x=-1,-3/2
①(2x-1)(x+1)=(3x+1)(x+1)
(3x+1)(x+1)-(2x-1)(x+1)
=(3x+1-2x+1)(x+1)
=(x+2)(x+1)=0
x=-1,-2
②(2x+1)^2+3(2x+1)+2=0
((2x+1)+1)((2x+1)+2)=0
2(x+1)(2x+3)=0
x=-1,-3/2