Question

Seja f uma função real com o domínio real, dada pela lei f(x) = x² - 4x + 3.calcule f(0)

Answer 1

f(0) = 0²-4*0+3
f(0) = 0 + 0 + 3
f(0) = 3

f(3/2) = (3/2)² - 4 * 3/2 + 3
f(3/2) = 9/4 - 12/2 +3 
f(3/2) = 9/4 - 24/4 + 12/4 
f(3/2) = 9/4 - 12/4
f(3/2) = 3/4

f(2) = 2² - 4*2 + 3
f(2) = 4 - 8 + 3
f(2) = -1

f(4) = 4² - 4*4 +3 
f(4) = 16 - 16 + 3
f(4) = 3

f(2) + f(4) = -1 + 3 = 2

f(-2) = -2² - 4 * -2 + 3
f(-2) = 4 + 8 + 3
f(-2) = 15

f(4) = 4² - 4 * 4 + 3
f(4) = 16 -16 + 3
f(4) = 3

f(-2) - f(4) = 15 - 3 = 12