Question

Encontre o vigesimo termo de P.A (3,8...)

Answer 1

razão = a2-a1 = 8-3 = 5

$a_n=a_1+(n-1)*r\\\\ a_2_0=3+19*5\\\\ a_2_0=3+95\\\\ \boxed{a_2_0=98}$

Answer 2

an=a1+(n-1)r
a20=3+(20-1)5
a20=3+19*5
a20=3+95
a20=98