Question

Determine o 40° termo de P.A (2,8,14,20,...)

Answer 1

a1=2

r=6

an=?

n=40

an=a1+(n-1)*r
an=2+(40-1)*6
an=2+(39)*6
an=2+234
an=236

Answer 2

$an=a1+(n-1).r a_{40}=2+(40-1).6 a_{40}= 2 + 39. 6 a_{40}= 2 + 234 a_{40}= 236$