Răspuns:
a)
[tex]x {}^{3} - 1 {}^{3} = x {}^{3} - 1[/tex]
b)
[tex]x {}^{3} + 1 {}^{3 } = x {}^{3} + 1[/tex]
c)
[tex](x {}^{2} + 1) {}^{2} - x {}^{2} \\ x {}^{4} + 2x {}^{2} + 1 - x { }^{2} \\ \\ {} x {}^{4} + x {}^{2} + 1[/tex]
d)
[tex](x {}^{2} - 1) \times (x - 2) \times (x + 2) \\ (x {}^{2} - 1) \times (x {}^{2} - 4) \\ x {}^{4} - 4x {}^{2} - x {}^{2} + 4 \\ x {}^{4} - 5x {}^{2} + 4[/tex]
Am pus direct rezolvarea