Question

Dada a função f(x) = 3x^2 - 7x + 15, calcule f(0) - f(1) + f(-1).

Answer 1

3.0²-7.0+15= 15
3.1²-7.1+15= 11            
3.(-1)²-7.(-1)+15= 25
15-11+25=29

Answer 2

Dada a função f(x) = 3x^2 - 7x + 15,
 calcule f(0) - f(1) + f(-1).

1º) achar o f(0)
f(x) = 3x² - 7x + 15
f(0) = 3(0)² - 7(0) + 15
f(0) =   0     - 0     + 15
f(0) = 15

2º) ACHAR o f(1)
f(x) = 3x² - 7x + 15
f(1) = 3(1)² - 7(1) + 15
f(1) = 3(1)  - 7      + 15
f(1) = 3 - 7 + 15
f(1) = 3+15 - 7
f(1) = 18 - 7
f(1) = 11

3º) ACHAR o f(-1)
f(x) = 3x² - 7x + 15
f(-1) = 3(-1)² -7(-1) + 15
f(-1) = 3(+1) + 7 + 15
f(-1) = 3 + 7 + 15
f(-1) = 25

então

f(0) = 15
f(1) = 11
f(-1) = 25

f(0) - f(1) + f(-1) =
15  - 11   + 25 =
15 + 25 - 11 =
        40 - 11 =  29

f(0) - f(1) + f(-1) = 29