T1 + T2 + T3 = 82
T2 = 2 × T1 + 3
T3 = 2 × ( 2 × T1 + 3) + 3
Inlocuim in suma termenilor in functie de T1
T1 + 2 × T1 + 3 + 4 × T1 + 6 + 3 = 82
7 × T1 = 82 - 12
7 × T1 = 70
T1 = 70 : 7
T1 = 10 (primul termen)
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T2 = 2 × 10 + 3 = 23 (al 2-lea termen)
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T3 = 2 × 23 + 3 = 46 + 3 = 49 (al 3-lea termen)
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82 = 10 + 23 + 49
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