Tentukan jumlah barisan bilangan barikut 5, 11, 17, 23,. ..........., 131

5, 11, 17, 23, ..., 131

a = 5

b = 11 - 5 = 6

Un = a + (n - 1)b

131 = 5 + (n - 1)(6)

131 = 5 + 6n - 6

131 = -1 + 6n

6n = 131 + 1

6n = 132

n = 132 ÷ 6

n = 22

Sn = [tex]\frac{n}{2}[/tex](a + Un)

S₂₂ = [tex]\frac{22}{2}[/tex](5 + 131)

S₂₂ = 11(136)

S₂₂ = 1.496