Question

Calcule a soma dos 76 primeiros termos naturais impares.
P.A

Answer 1

1,3,5,.......

n=76
razão=r=2

an=a1+(n1)*r
a76=1+(76-1)*2=151

Sn=(a1+an)*n/2
S76=(1+151)*76/2 =5.776

Answer 2

resolução!

an = a1 + ( n - 1 ) r

an = 1 + ( 76 - 1 ) 2

an = 1 + 75 * 2

an = 1 + 150

an = 151

Sn = ( a1 + an ) n / 2

Sn = ( 1 + 151 ) 76 / 2

Sn = 152 * 38

Sn = 5776