Question

numa p.g de primeiro termo igual 6 e ultimo termo 216. Tendo essa sequencia apenas tres termos calcule a soma​

Answer 1

$\large\boxed{\begin{array}{l}\rm(6,x,216)\\\rm  x^2=6\cdot216\\\rm x^2=1296\\\rm x=\sqrt{1296}\\\rm x=36\\\rm 6+36+216=258\end{array}}$