1.(X+Y)(X+Y+2XY)+(XY+1)XY-1)
2.X^2-Y^2-2X-4Y-3
3.(XY-1)^2+(X+Y-2)(X+Y-2XY)
4.X^4(Y^2-Z^2)+Y^4(Z^2-X^2)+Z^4(X^2-Y^2)
5.a^3*x^2n+1+8a^2*x^2n+5+16ax^2n+9
6.ab(a+b)^2-(a+b)^2+1
7.(X+Y)+(X^2-Y^2)^2+(X-Y)^4
1.(X+Y)(X+Y+2XY)+(XY+1)XY-1)
2.X^2-Y^2-2X-4Y-3
3.(XY-1)^2+(X+Y-2)(X+Y-2XY)
4.X^4(Y^2-Z^2)+Y^4(Z^2-X^2)+Z^4(X^2-Y^2)
5.a^3*x^2n+1+8a^2*x^2n+5+16ax^2n+9
6.ab(a+b)^2-(a+b)^2+1
7.(X+Y)+(X^2-Y^2)^2+(X-Y)^4