Explicație pas cu pas:
[tex]2a {}^{3} + 2ab {}^{2 } - 2b(a {}^{3} + 2ab) + 3ab {}^{2} [/tex]
[tex]2a {}^{3} b + 2ab {}^{2} - (2ba {}^{3} + 4b { }^{2} a) + 3ab {}^{2} [/tex]
[tex]2a {}^{3} b + 2ab {}^{2} - 2ba {}^{3} - 4b {}^{2} a + 3ab {}^{2} [/tex]
[tex](2a {}^{3} b - 2a {}^{3} b) + (2ab {}^{2} - 4ab {}^{2} + 3ab {}^{2} )[/tex]
[tex]ab {}^{2} [/tex]
