Question

Escreva a PA de 6 termos, em que a3=4 e a razão e r=1/2

Answer 1

a3=4
r=1/2

an=a1+(n-1).r
a3=a1+(3-1).1/2
4=a1+2.1/2
4=a1+1
a1=4-1
a1=3

a1=3
a2=3+1/2=6/2+1/2=7/2
a3=7/2+1/2=8/2=4
a4=4+1/2=8/2+1/2=9/2
a5=9/2+1/2=10/2=5
a6=5+1/2=10/2+1/2=11/2