Question

Determine o quadragésimo primeiro termo da progressão aritmética (1,3,5,7,...)

Answer 1

an = a1 + (n - 1) . r → a41 = a1 + (n - 1) . r → a41 = 1 + (41 - 1) . 2 →
a41 = 1 + 40 . 2 → a41 = 1 + 80 → a41 = 81

P.A (1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81)