Question

Determinati numarul real x, stiind ca numerele x+1, x^2+1 si x^3-1 sunt termeni consecutivi ai unei progresii aritmetice.

Answer 1

2(x²+1)=x+1+x³-1
2x²+2=x³+x
x³-2x²+x-2=2
x²(x-2)+(x-2)=0
(x-2)(x²+1)=0
x-2=0
x=2