Question

ajuda questão 17 por favor ...
obs : PA

Answer 1

a 34 = 92
r  = 3
a 34 = a 1 + ( n - 1 ) . 3
a 34 = a 1 + (34 - 1). 3
a 34 = a 1 + 33 . 3
a 34 = a 1 + 99
a 1 + 99 = 92
a 1 = 92 - 99
a 1 = -7
b)a 31 = a 1 + (n - 1 ).r
a 31 = a 1 + (31 - 1 ) . -4
a 31 = a 1+ (30 . -4 )
a 31 = a 1 + (-120)
a 31  = a 1 - 120
a 1 - 120 = 81
a 1 = 81 + 120
a 1 = 201
c)a 27 = 16
r = 1/2
a 27 = a 1 + (n - 1 ) . r
a 27 = a 1 + (27 - 1 ) . 1/2
a 27 = a 1 + 26 . 1/2
a 27 = a 1 + 13
a 1 + 13 = 16
a 1 = 16 - 13
a 1 = 3