Suatu barisan Aritmatika diketahui U₂ = -1 dan U5 8. Tentukan : == a. suku pertama Jawab : b. beda c. suku ke-30
![]()
a.) Suku pertama
U2 = a + b = -1 |×4| 4a + 4b = -4
U5 = a + 4b = 8 |×1| a + 4b = 8
__________________________-
3a = -12
a = -4
b.) Beda
a + b = -1
b = -1 - a
b = -1 - (-4)
b = -1 + 4
b = 3
c.) Suku ke 30
Un = a + (n - 1)b
U30 = -4 + (30 - 1)(3)
U30 = -4 + 29(3)
U30 = -4 + 57
U30 = 53
[tex]\purple{\boxed{\blue{\boxed{\green{\star{\orange{\ \: \: \mathcal{JK} \: \: \: {\green{\star}}}}}}}}} [/tex]
[answer.2.content]
