Răspuns:
[tex]t {}^{12} + z {}^{9} = (t {}^{4}) {}^{3} + (z {}^{3} ) {}^{3} =(t {}^{4} + z {}^{3} )((t {}^{4} ) {}^{2} - t {}^{4} z {}^{3} + (z {}^{3} ) {}^{2} ) = (t {}^{4} + z {}^{3} )(t {}^{8} - t {}^{4} z {}^{3} + z {}^{6} )[/tex]
