Question

Ache numa P.A., sabendo que R= 1/4 e A17=21. (cálculo)

Answer 1

a17 = a1+16.r
21 = a1+16.1/4
21 = a1+4
a1 = 4-21
a1 = -17
n = 17

PA = (-17, -67/4, -66/4, -65/4, -64/4, -63/4, -62/4, -61/4, -60/4, -59/4, -58/4, -57/4, -56/4, -55/4, -54/4..., -80/4, -69/4, -68/4)