Question

determine a formula do termo geral de cada PA
(-1,5,...)

Answer 1

r = 5 -(-1) = 6
an = a1 + (n -- 1)r

an = -1 + (n-1)6
an = -1 + 6n - 6
an = 6n - 7

Answer 2

a1= - 1

r= 5 - ( - 1) = 6

an= a1 + (n - 1) • r

an= - 1 + (n - 1) • 6

an= - 1 + 6n - 6

an= 6n - 7