We have $y^3 + 2y + 1 > y^3$
Further $(y+2)^3 = y^3 + 6y^2 + 12y + 8 > y^3 + 2y + 1$
So we have $(y+2)^3 > x^3 > y^3$
So $x^3 = (y+1)^3 = y^3 + 3y^2 + 3y +1 = y^3 + 2y + 1$
Or $3y^2 + 3y + 1 = 2y + 1$
Or $3y^2 + y = 0$
Or y = 0 as we are considering non -ve roots
So solution x=1, y = 0
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