Simplify: (x3+3x2−2x)+(−x3+x2+5x)(x^3 + 3x^2 - 2x) + (-x^3 + x^2 + 5x)(x3+3x2−2x)+(−x3+x2+5x).
4x2+3x4x^2 + 3x4x2+3x
4x2−7x4x^2 - 7x4x2−7x
2x3+4x2+3x2x^3 + 4x^2 + 3x2x3+4x2+3x
4x2+7x4x^2 + 7x4x2+7x