Question

Dada a função f (x) = 8x + 15, calcule:a) f(0) – f(3)b) f(5) – f (10)c) f(7) + f(-3)d) f(2) + f( 3)

Answer 1

f (x) = 8x + 15, calcule:

a) f(0) – f(3)  = 15 - 39 = - 24

f(0) = 8.0 + 15
f(0) = 15

f(3) = 8.3 + 15
f(3) = 24 + 15
f(3) = 39

R.: f(0) - f(3) = - 24

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b) f(5) – f (10) =55 - 95 = - 95 + 55 = - 40

f(5) = 8.5 + 15
f(5) = 40 + 15
f(5) = 55

f(10) = 8.10 + 15
f(10) = 80 + 15
f(10) = 95

R.: f(5) - f(10) = 55 - 95 = - 40

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c) f(7) + f(-3) = 71 - 9 = 62

f(7) = 8.7 + 15
f(7) = 56 + 15
f(7) = 71

f(-3) = 8.(-3) + 15
f(-3) = - 24 + 15
f(-3) = - 9

R.: f(7) - f(3) = 62
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d)

f(2) + f( 3) = 31 + 39 = 70

f(x) = 8x + 15
f(2) = 8.2 + 15
f(2) = 16 + 15
f(2) = 31

f(x) = 8x + 15
f(3) = 8.3 + 15
f(3) = 24 + 15
f(3) = 39

R.: f(2) + f(3) = 31 + 39 =70