Question

E(x)=x la a treia+(x+1) la a doua+2(x-3)(x+3)+17
aratati ca E(x) e multiplu de 6 , pentru orice numar natural n.

Answer 1

E(x)=x³+(x+1)²+2(x-3)+17
E(x)=x³+x²+2x+1+2x²-18+17
E(x)=x³+3x²+2x
E(x)=x(x²+3x+2)
E(x)=x(x+1)(x+2)