diketahui arirmatika = 17,20,23,26,29. tentukan u30 dan s30

a=17, b=3, n=30
U30= rumusnya ; Un=a+(n-1)b
U30= 17+(30-1)3
=17+(29)3
=17+87=104

Sn= 1/2n(2a+(n-1)b)
S30=1/2.30(2.17+(30-1)3)
=15(34+(29)3)
=15(34+87)
=15(121)=1815

Diketahui :
a = 17
b = 20-17 =3

# Aritmatika
• U30
Un = a + (n-1) b
U30 = 17 + (30-1) 3
= 17 + (29) 3
= 17 + 87 = 104

• S30
Sn = n/2 (2a + (n-1) b)
S30 = 30/2 (2(17) + (30-1) 3)
= 15 (34 + (29) 3)
= 15 (34 + 87)
= 15 (121)
= 1815