Question

o numero de termos da PA (12,19,26,...,656)

Answer 1

o numero de termos da PA (12,19,26,...,656)


an=285
a1=12
n=?
r=7


an=a1+(n-1)*r

285=12+(n-1)*7
285-12=7n-7
273+7=7n
280=7n
n=280/7
n=40

R: 41 termos

Answer 2

an= a1 + (n - 1) * r

656= 12 + (n - 1) * 7
656= 12 + 7n - 7
651 = 7n
n = 93 termos