bantu lagi @andilufpi tentukan beda dan suku pertama serta U10 jika U3 = 3 dan U5 = 7

Aritmatika

b = (U5 - U3) / (5 - 3)
b = (7 - 3) / 2
b = 4 / 2
b = 2

U3 = U1 + 2b
U1 = U3 - 2b
U1 = 3 - 2(2)
U1 = 3 - 4
U1 = -1

U10 = U5 + 5b
U10 = 7 + 5(2)
U10 = 7 + 10
U10 = 17

Semoga berguna +_+

Materi : Barisan dan deret

Pembahasan :
U5 = 7
a + 4b = 7

U3 = 3
a + 2b = 3

Eliminasi...
a + 4b = 7
a + 2b = 3
——————— (-)
2b = 4
Beda = 2

Substitusi...
a + 2b = 3
a + 2(2) = 3
a = 3 - 4
Suku Pertama = -1

U10 = a + 9b
U10 = -1 + 9(2)
U10 = -1 + 18
U10 = 17