Question

ARITEMATIKA

1. 51 + 53 + 55 + 57 + 59 .... + 99 =
2. 1 + 2 + 3 + 4 + 5 ... 2019 = ...
3. 2 + 4 + 6 + 8 + 10 ... + 50 = ...​

Answer 1

Penjelasan dengan langkah-langkah:

Answer 2

Jawaban

1.) 1.875

2.) 2.039.190

3.) 650

Rumus barisan aritmatika

Rumus deret aritmatika

Langkah langkah

No. 1

51 + 53 + 55 + 57 + 59 ... + 99 = ...

b = 53-51 = 2

Un = a + (n - 1)b

99 = 51 + (n - 1)2

99 = 51 + 2n - 2

-2n = 51 - 91 - 2

-2n = -50

n = -50/-2

n = 25

Sn = n/2 (a + Un)

Sn = 25/2 (51 + 99)

Sn = 25/2 (150)

Sn = 25 (75)

Sn = 1.875

No. 2

1 + 2 + 3 + 4 + 5 ... + 2019 = ...

b = 2-1 = 1

Un = a + (n - 1)b

2019 = 1 + (n - 1)1

2019 = 1 + 1n - 1

-1n = -2019

n = -2019/-1

n = 2019

Sn = n/2 (a + Un)

Sn = 2019/2 (1 + 2019)

Sn = 2019/2 (2020)

Sn = 2019 (1010)

Sn = 2.039.190

No. 3

2 + 4 + 6 + 8 + 10 ... + 50 = ...

b = 4-2 = 2

Un = a + (n - 1)b

50 = 2 + (n - 1)2

50 = 2 + 2n - 2

-2n = -50

n = -50/-2

n = 25

Sn = n/2 (a + Un)

Sn = 25/2 (2 + 50)

Sn = 25/2 (52)

Sn = 25 (26)

Sn = 650

Pelajari lebih lanjut

Contoh soal barisan aritmatika

• brainly.co.id/tugas/21219611
• brainly.co.id/tugas/22992183

Contoh soal deret aritmatika

• brainly.co.id/tugas/22304204
• brainly.co.id/tugas/23092023

Detail Jawaban

• Kelas : 9
• Mapel : Matematika
• Bab : 2-Barisan dan deret bilangan
• Kode : 9.2.2
• Kata Kunci : Barisan dan Deret Aritmatika