Question

Determine o 15° termo da PG (256,128,46...)

Answer 1

$PG (256,128,46...)\\\\ a_n=a_{15}=?\\a_1=256\\ n=15\\ q= \frac{128}{256} \to \frac{1}{2} \\\\\\ a_n=a_1*q^{n-1}\\\\\\ a_{15}=256* \frac{1}{2}^{15-1} \to\\\\ a_{15}=256* \frac{1}{2}^{14} \to \\\\ a_{15}=256* \frac{1}{16384}\to \\\\a_{15}=256* \frac{256}{16384}\to \\\\a_{15}= \frac{1}{64}$