Question

c1=-5, cn+1=cn-2
Найдите c7

Answer 1

c8 = c7 - 2

c2 = c1 - 2 = -5 - 2 = -7

c3 = c2 - 2 = -7 - 2 = -9

c4 = c3 - 2 = -9 - 2 = -11

c5 = c4 - 2 = -11 - 2 = -13

c6 = c5 - 2 = -13 - 2 = -15

c7 = c6 - 2 = -15 - 2 = -17

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| c8 = c7 - 2 = -17 - 2 = -19 |

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