Răspuns:
Explicație pas cu pas:
f(x) = 2 x - 4
f(0) = 2 × 0 - 4 = - 4
f(1) = 2 × 1 - 4 = - 2
f(2) = 2 × 2 - 4 = 0
f(3) = 2 × 3 - 4 = 2
f(4) = 2 × 4 - 4 = 4
f(5) = 2 × 5 - 4 = 6
f(6) = 8
f(7) = 2 × 7- 4 = 10
f(8) =12
f(9) = 14
f(10) = 16
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f(0) + f(1) + f(2) + f(3) + ....... + f(10) = 66
= - 4 - 2 + 0 + 2 + 4 + 6 + ...... + 14 + 16 =
= - 6 + 2 × ( 1 + 2 + 3 + ..... + 8) =
= - 6 + 2 × 8 × 9 : 2 =
= - 6 + 72 =
= 66
