Question

escreva a pa tal que a,=3 e r=-4;com oito termos

Answer 1

A8=A1+7*r
A8=3+7*-4
A8=3+(-28)
A8=-25

Answer 2

a8=a1+(n-1).r

a8=3+(8-1).(-4)

a8=3+(7)(-4)

a8=3+(-28)

a8=3-28
a8=-25

P.A (3,-1,-5,-9,-13,-17,-21,-25)