Pertanyaan

Tentukan banyaknya suku untuk setiap barisan geometri berikut ini. c. 4 1 , 12 1 , 36 1 , ... , 8.748 1

Tentukan banyaknya suku untuk setiap barisan geometri berikut ini.

c. $\frac{1}{4}, \frac{1}{12}, \frac{1}{36}, ..., \frac{1}{8.748}$

W. Lestari

Master Teacher

Mahasiswa/Alumni Universitas Sriwijaya

Jawaban terverifikasi

Jawaban

banyaknya suku barisan tersebut adalah 8.

Pembahasan

Jadi, banyaknya suku barisan tersebut adalah 8.

$begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row a equals cell 1 fourth end cell row r equals cell fraction numerator begin display style 1 over 12 end style over denominator begin display style 1 fourth end style end fraction equals 1 third end cell row cell U subscript n end cell equals cell fraction numerator 1 over denominator 8.748 end fraction end cell row blank blank blank row cell U subscript n end cell equals cell a times r to the power of n minus 1 end exponent end cell row cell fraction numerator 1 over denominator 8.748 end fraction end cell equals cell 1 fourth times open parentheses 1 third close parentheses to the power of n minus 1 end exponent end cell row cell open parentheses 1 third close parentheses to the power of n minus 1 end exponent end cell equals cell fraction numerator fraction numerator 1 over denominator 8.748 end fraction over denominator 1 fourth end fraction end cell row cell open parentheses 1 third close parentheses to the power of n minus 1 end exponent end cell equals cell fraction numerator 1 over denominator 2.187 end fraction end cell row cell open parentheses 1 third close parentheses to the power of n minus 1 end exponent end cell equals cell open parentheses 1 third close parentheses to the power of 7 end cell row cell n minus 1 end cell equals 7 row blank rightwards double arrow cell n equals 8 end cell end table end style$

Jadi, banyaknya suku barisan tersebut adalah 8.