Question

Determine o 12° termo da P.A (4, 9, 14, 19, 24, 29, ...)

Answer 1

r = a₂ - a₁
r = 9 -4   → 5

$A_{n} = a_{1} + (n -1) . r$
a₁₂ = 4 + 11 . 5
a₁₂ = 4 + 55
a₁₂ = 59