Question

3. Determine o termo geral da PA (8, 12, 16, 20,...).
a) an = -4n+4
b) an = 4n+ 4
c) an = -4n4
d) an = 4n - 4 3. ​

Answer 1

$> \: resolucao \\ \\ \geqslant \: progressao \: \: aritmetica \\ \\ r = a2 - a1 \\ r = 12 - 8 \\ r = 4 \\ \\ \\ an = a1 + (n - 1)r \\ an = 8 + (n - 1)4 \\ an = 8 + 4n - 4 \\ an = 4n + 4 \\ \\ \\ resposta \: \: > \: \: letra \: \: ( \: \: \: b \: \: \: ) \\ \\ \geqslant \leqslant \geqslant \leqslant \geqslant \leqslant \geqslant \leqslant \geqslant \geqslant \geqslant$