Answer:
or, 2x-x^2+2x^2=1
or,2x+x^2=1
or,x^2+2x-1=0
or,x^2+x+x-1=0
or,x(x+1)+1(x-1)=0
or,(x+1)(x-1)=0
therefore x=(-1,+1)
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