diketahui suatu barisan aritmatka denagan suku pertama -15 dan suku ke limanya 1 a. tentukan beda barisan aritmatika tersebut b.tentuka suku ke 10 c. tuliskan 1

1. Jawab yang A

U1 = a = -15
U5 = a + 4b = 1 (masukan nilai a)
-15 + 4b = 1
4b = 1 + 15
4b = 16
b = 16 ÷ 4
b = 4

2. jawab yang B
U10 = a + 9b
U10 = -15 + 9(4)
U10 = -15 + 36
U10 = 21

3. Jawab yang C
U1 = a = -15
U2 = a + b = -15 + 4 = -11
U3 = a + 2b = -15 + 8 = -7
U4 = a + 3b = -15 + 12 = -3
U5 = a + 4b = -15 + 16 = 1
U6 = a + 5b = -15 + 20 = 5
U7 = a + 6b = -15 + 24 = 9
U8 = a + 7b = -15 + 28 = 13
U9 = a + 8b = -15 + 32 = 17
U10 = a + 9b = -15 + 36 = 21