Question

Dadas as funções f (x)= 2x² -6x - 4 e g(x) = -3x² -5x +1 calcule: a) f(3), b) f(-2), c) f(0), d) f(-0,2), e) g(1), f) g(-4), g) g (0), h) g(1/2)

Answer 1

Dadas as funções

f(x)= 2x² -6x - 4

g(x) = -3x² -5x + 1

calcule:

a)

f(x) = 2x² - 6x - 4

f(3) = 2.3² - 6.3 - 4

f(3) = 2.9 - 18 - 4

f(3) = 18 - 18 - 4

f(3) = - 4

b)

f(x)= 2x² -6x - 4

f(-2) = 2.(-2)² - 6.(-2) - 4

f(-2) = 2.4 + 12 - 4

f(-2) = 8 + 12 - 4

f(-2) = 20 - 4

f(-2) = 16

c)

f(x)= 2x² -6x - 4

f(0) = 2.0² - 6.0 - 4

f(0) = - 4

d)

f(x)= 2x² -6x - 4

f(-0,2) = 2.(-0,2)² - 6.(-0,2) - 4

f(-0,2) = 2.0,04 + 1,2 - 4

f(-0,2) = 0,08 + 1,20 - 4,00

f(-0,2) = 1,28 - 4,00

f(-0,2) = - 2,72

e)

g(x) = -3x² -5x + 1

g(1) = - 3.1² - 5.1 + 1

g(1) = - 3 - 5 + 1

g(1) = - 7

f)

g(x) = -3x² -5x + 1

g(-4) = - 3.(-4)² - 5.(-4) + 1

g(4) = - 3.16 + 20 + 1

g(4) = - 48 + 21

g(4) = - 27

g)

g(x) = -3x² -5x + 1

g (0) = - 3.0² - 5.0 + 1

g(0) = 1

h)

g(x) = -3x² -5x + 1

g(1/2) = - 3.(1/2)² - 5.(1/2) + 1

g(1/2) = - 3 . 1/4 - 5/2 + 1

g(1/2) = - 3/4 - 5/2 + 1

g(1/2) = (-3 - 2.5 + 4.1)/4

g(1/2) = (-3 - 10 + 4)/4

g(1/2) = - 9/4