Odpowiedzi

Najlepsza Odpowiedź!
2009-11-05T19:45:05+01:00
A) D: x∉R \ 2

x³ - 8 / 2 - x = (x - 2)(x² + 2x + 2)/-(x -2) = -(x² +2x +2)

b) D: x∉R \ 2, -2

x² + 4x + 4/x² -4 = (x +2)²/(x-2)(x+2) = (x+2)/(x-2)

c) D: x∉R \ 1 i - 1

x² - 2x - 3/ (x+1)(x-1)
Δ = 4 + 12 = 16
x₁= 2 + 4/2 = 3
x₂= 2 - 4/2 = -1

(x+1)(x-3)/(x+1)(x-1) = x-3/x-1

d) D: x∉R \ 1 i -1

x³ - x² - x + 1 / x⁴- 2x² + 1 = x²(x - 1) - 1(x-1)/(x²-1)² =
= (x-1)(x²-1)/(x²-1)² = (x-1)/(x²-1) = 1/(x+1)
1 5 1