Jumlah 10 suku pertama ,dari deret 3+7+11+15 Adalah

langsung aja y

a = 3
b = 7 - 3 = 4

S10 = 10/2 (2a + 9b)
S10 = 5(2.3 + 9.4)
S10 = 5(6+36)
S10 = 5(42)
S10 = 210

semoga berguna +_+

U10 = a + ( n - 1 ) b
U10 = 3 + ( 10 - 1 ) 4
U10 = 3 + ( 9 ) 4
U10 = 3 + 36
U10 = 39

U = Suku
a = Suku pertama
b = beda antar suku