Question

_DESAFIO_Escreva a PA de r =3 e a22 = 52

Answer 1

an = a1 + (n-1)*r
a22 = a1 + (22 - 1)*r
52 = a1 + 21*3
a1 = -11

-11 , -8, -5, -2, 1, 4, ... , 52 , 55 ,  ...

Answer 2

an = ak + ( n - k ) * r
an = 52 + ( 1 - 22 ) * 3
an = 52 + ( -21 ) * 3
an = 52 - 63
an = -11


PA ( -11; -8 ; -5 ; -2 ; 1 ; .... ; 52 )