Question

Wyznacz zbiór wartości funkcji.
a) f(x) = 3-5x D = {0,1,,2}
b) f(x) = 3 - 5x +2 D= {-2,-1,0,1,2}

Answer 1

A)
f(x) = 3 - 5x          D = {0, 1, V2, 2}

f(0) = 3 - 5 * 0 = 3 - 0 = 3
f(1) = 3 - 5 * 1 = 3 - 5 = -2
f(V2) = 3 - 5 * V2 = 3 - 5V2
f(2) = 3 - 5 * 2 = 3 - 10 = - 7

ZW = {-7, 3-5V2, -2, 3}

b)
f(x) = 3x^2 - 5x + 2      D = {-2, -1, 0, 1, 2}

f(-2) = 3 *(-2)^2 - 5 *(-2) + 2 = 12 + 10 + 2 = 24
f(-1) = 3 * (-1)^2 - 5 *(-1) + 2 = 3 + 5 + 2 = 10
f(0) = 3 * 0^2 - 5 * 0 + 2 = 0 - 0 + 2 = 2
f(1) = 3 * 1^2 - 5 *1 + 2 = 3 - 5 + 2 = 0
f(2) = 3 * 2^2 - 5 * 2 + 2 = 12  - 10 + 2 = 4

ZW = {0, 2, 4, 10, 24}


(V - pierwiastek kwadratowy)