Question

Barisan aritmatika u3= 18 u7=38 jumlah 24 suku pertama

Answer 1

Materi Baris Deret
Kelas IX

U7 = a + 6b = 38
U3 = a + 2b = 18
       ___________ - 
               4b = 20
                 b = 5
a +10 = 18
a = 8
U24 = a + 23b 
= 8 + 23.5
= 123
Sn = n/2 (a+Un)
S24 = 24/2 (8+123)
S24 = 12.131 = 1572

Mohon maaf apabila ada kesalahan