Question

Determine o 41° termo da P.A.(3,6,9,..).

Answer 1

a1 = 3
a2 = 6
a3 = 9
r = 6 - 3 = 3

a41 =  a1 + 40r **

3 + 40 ( 3 )  = 3 + 120 = 123 ***

Answer 2

Determine o 41° termo da P.A.(3,6,9,..).

R = A2 - A1
R = 6 - 3
R = 3

An = A1 + (n - 1)*r
A41 = 3 + (41 - 1)*3
A41 = 3 + 40*3
A41 = 3 + 120
A41 = 123

PA = {3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60,63,66,69,72,75,78,82,85,88,91,94,97,100,103,106,109,112,115,118,121,123}

Resposta : A41 = 123