Question

1. Wielomianowi W(x)= -2x³-4x²+x+2,przyporządkuj jego rozkład na czynniki

a)(x+2)(2x²-1)

b)-(x+2)(2x²-1)

c)(x-2)(2x²+1)

d)-(x-2)(2x²+1)

2.Jeśli f(x)= x³-2x²-9x-1 to:

a) f(-2) = f(2)

b) f(-2) ≤ f(2)

c) f(-2) < f(2)

d f(-2) > f(2)

Answer 1

1)

W(x)= -2x³-4x²+x+2 = -2x²(x+2)+x+2 = (x+2)(-2x²+1)=(x+2)(1-2x²) =(x+2)*-(2x²-1)=-(x+2)(2x²-1)

 

odp. B

 

2)

f(x)= x³-2x²-9x-1

f(2) = 2³-2*2²-9*2-1 = 8-8-19=-19

f(-2)=(-2)³-2*(-2)²-9*(-2)-1 = -8-8+18-1 = -16+17 = 1

 

1>-19 => f(-2)>f(2)

odp. D

 

 

 

Answer 2

zad.1:

-2x³-4x²+x+2 = -2x²(x+2)+(x+2) = (x+2)(1-2x²)=-(x+2)(2x²-1)

odp. B

 

zad. 2:

f(x)= x³-2x²-9x-1

f(2) = 8-8-18-1=-19

f(-2) = -8-8+18-1 = 17-16 = 1

f(-2)>f(2)

odp. D