Odpowiedzi

2009-11-22T09:53:00+01:00
F(x)=1/(x³-7x²-2x+14)

x³-7x²-2x+14=0
x²(x-7)-2(x-7)=(x-7)(x²-2)=(x-7)(x-√2)(x+√2)=0
zatem
x=7 , x=-√2 i x=√2

Dziedzina : x∈R/{-√2,√2,7}
2009-11-22T10:49:15+01:00
F(x)=1/(x³-7x²-2x+14)
x³-7x²-2x+14≠0
x²(x-7)-2(x-7)≠0
(x²-2)(x-7)≠0
(x-√2)(x+√2)(x-7)≠0
x≠√2∧ x≠-√2 ∧x≠7
D=R\{-√2,√2,7}