Iklan

Pertanyaan

Buktikan dengan induksi matematika bahwa rumus berikut berlaku untuk setiap bilangan asli! b.

Buktikan dengan induksi matematika bahwa rumus berikut berlaku untuk setiap begin mathsize 14px style n end style bilangan asli!

b. begin mathsize 14px style 1 half plus 2 over 4 plus 3 over 8 plus 4 over 16 plus... plus n over 2 to the power of n equals 2 minus fraction numerator n plus 2 over denominator 2 to the power of n end fraction end style

Ikuti Tryout SNBT & Menangkan E-Wallet 100rb

Habis dalam

00

:

01

:

23

:

00

Klaim

Iklan

N. Puspita

Master Teacher

Jawaban terverifikasi

Jawaban

rumus berlaku untuk setiap bilangan asli.

 rumus begin mathsize 14px style 1 half plus 2 over 4 plus 3 over 8 plus 4 over 16 plus... plus n over 2 to the power of n equals 2 minus fraction numerator n plus 2 over denominator 2 to the power of n end fraction end style berlaku untuk setiap begin mathsize 14px style n end style bilangan asli.

Pembahasan

Pembahasan
lock

Perhatikan perhitungan berikut ini. 1. Akan dibuktikan untuk adalah benar, maka: Benar untuk 2. Asumsikan , maka: Akan dibuktikan benar, sehingga: Pembuktian: Terbukti. Jadi,rumus berlaku untuk setiap bilangan asli.

Perhatikan perhitungan berikut ini.

begin mathsize 14px style 1 half plus 2 over 4 plus 3 over 8 plus 4 over 16 plus... plus n over 2 to the power of n equals 2 minus fraction numerator n plus 2 over denominator 2 to the power of n end fraction end style

1. Akan dibuktikan untuk begin mathsize 14px style n equals 1 end style adalah benar, maka:

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell 1 half end cell equals cell 2 minus fraction numerator n plus 2 over denominator 2 to the power of n end fraction end cell row cell 1 half end cell equals cell 2 minus fraction numerator 1 plus 2 over denominator 2 to the power of 1 end fraction end cell row cell 1 half end cell equals cell 2 minus 3 over 2 end cell row cell 1 half end cell equals cell fraction numerator 4 minus 3 over denominator 2 end fraction end cell row cell 1 half end cell equals cell 1 half end cell end table end style

Benar untuk begin mathsize 14px style n equals 1 end style

2. Asumsikan begin mathsize 14px style n equals k end style, maka: 

begin mathsize 14px style 1 half plus 2 over 4 plus 3 over 8 plus 4 over 16 plus... plus k over 2 to the power of k equals 2 minus fraction numerator k plus 2 over denominator 2 to the power of k end fraction end style

Akan dibuktikan begin mathsize 14px style n equals k plus 1 end style benar, sehingga:

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell 1 half plus 2 over 4 plus 3 over 8 plus 4 over 16 plus... plus k over 2 to the power of k plus fraction numerator k plus 1 over denominator 2 to the power of k plus 1 end exponent end fraction end cell equals cell 2 minus fraction numerator open parentheses k plus 1 close parentheses plus 2 over denominator 2 to the power of k plus 1 end exponent end fraction end cell end table end style

Pembuktian:

begin mathsize 14px style 1 half plus 2 over 4 plus 3 over 8 plus 4 over 16 plus... plus k over 2 to the power of k plus fraction numerator k plus 1 over denominator 2 to the power of k plus 1 end exponent end fraction space equals 2 minus fraction numerator k plus 2 over denominator 2 to the power of k end fraction plus fraction numerator k plus 1 over denominator 2 to the power of k plus 1 end exponent end fraction space equals 2 minus open parentheses fraction numerator k plus 2 over denominator 2 to the power of k end fraction minus fraction numerator k plus 1 over denominator 2 to the power of k plus 1 end exponent end fraction space close parentheses equals 2 minus open parentheses fraction numerator 2 open parentheses k plus 2 close parentheses over denominator 2 times 2 to the power of k end fraction minus fraction numerator k plus 1 over denominator 2 to the power of k plus 1 end exponent end fraction close parentheses space equals 2 minus open parentheses fraction numerator 2 k plus 4 over denominator 2 to the power of k plus 1 end exponent end fraction minus fraction numerator k plus 1 over denominator 2 to the power of k plus 1 end exponent end fraction space close parentheses equals 2 minus open parentheses fraction numerator 2 k plus 4 minus open parentheses k plus 1 close parentheses over denominator 2 to the power of k plus 1 end exponent end fraction close parentheses space equals 2 minus fraction numerator 2 k plus 4 minus k minus 1 over denominator 2 to the power of k plus 1 end exponent end fraction space equals 2 minus fraction numerator k plus 3 over denominator 2 to the power of k plus 1 end exponent end fraction space equals 2 minus fraction numerator open parentheses k plus 1 close parentheses plus 2 over denominator 2 to the power of k plus 1 end exponent end fraction end style

Terbukti.

Jadi, rumus begin mathsize 14px style 1 half plus 2 over 4 plus 3 over 8 plus 4 over 16 plus... plus n over 2 to the power of n equals 2 minus fraction numerator n plus 2 over denominator 2 to the power of n end fraction end style berlaku untuk setiap begin mathsize 14px style n end style bilangan asli.

Perdalam pemahamanmu bersama Master Teacher
di sesi Live Teaching, GRATIS!

1

Iklan

Pertanyaan serupa

Buktikan dengan induksi matematika. 2 1 ​ + 4 1 ​ + 8 1 ​ + ⋯ + 2 n 1 ​ = 1 − 2 n 1 ​

136

4.0

Jawaban terverifikasi

RUANGGURU HQ

Jl. Dr. Saharjo No.161, Manggarai Selatan, Tebet, Kota Jakarta Selatan, Daerah Khusus Ibukota Jakarta 12860

Coba GRATIS Aplikasi Roboguru

Coba GRATIS Aplikasi Ruangguru

Download di Google PlayDownload di AppstoreDownload di App Gallery

Produk Ruangguru

Hubungi Kami

Ruangguru WhatsApp

+62 815-7441-0000

Email info@ruangguru.com

[email protected]

Contact 02130930000

02130930000

Ikuti Kami

©2025 Ruangguru. All Rights Reserved PT. Ruang Raya Indonesia