Question

determine o sesctotermo da P.A. (4,7,10...)

Answer 1

$a_6=? \\ a_1=4 \\ n=6 \\ r=3$
$a_n=a_1+(n-1)r \\ a_6=4+(6-1)3 \\ a_6=4+5.3 \\ a_6=4+15=19 \\ \\ a_6=19$

$PA = (4-7-10-13-16-19)$