Question

Quantos termos tem a PA (7,12,17,...417)

Answer 1

$Dados:\\\\a_{1} = 7\\\\a_{n} = 417\\\\r = 12 - 7 = 5\\\\n = \: ?\\\\Formula \: do \: termo \: geral:\\\\a_{n} = a_{1} + (n - 1).r\\\\417 = 7 + (n - 1).5\\\\417 = 7 + 5n - 5\\\\5n = 417 - 7 + 5\\\\5n = 415\\\\n = \frac{415}{5}\\\\n = 83$

Resposta: 83 termos.

Espero ter ajudado!

Answer 2

$Dados:\\\\ a_{1} = 7\\\\ a_{n} = 417\\\\ r = 12 - 7 = 5\\\\ n = ?\\\\ Formula \: do \: termo \: geral:\\\\ a_{n} = a_{1} + (n - 1).r\\\\ 417 = 7 + (n - 1).5\\\\ 417 = 7 + 5n - 5\\\\ 5n = 417 - 7 + 5\\\\ 5n = 415\\\\ n = \frac{415}{5}\\\\ n = 83$

Resposta: 83 termos.

Espero ter ajudado!

Answer 3

$Dados:\\\\ a_{1} = 7\\\\ a_{n} = 417\\\\ r = 12 - 7 = 5\\\\ n = ?\\\\ Formula \: do \: termo \: geral:\\\\ a_{n} = a_{1} + (n - 1).r\\\\ 417 = 7 + (n - 1).5\\\\ 417 = 7 + 5n - 5\\\\ 5n = 417 - 7 + 5\\\\ 5n = 415\\\\ n = \frac{415}{5}\\\\ n = 83$

Resposta: 83 termos.

Espero ter ajudado!