Question

determine o 12º termo da P.A (3,5,1 ...)

Answer 1

an = a1 + (n - 1) x r

an = 3 + (12 - 1) x 2

an = 3 + 11 x 2

an = 3 + 22

an = 25

PA (3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25,..)