Question

bantuyu dongg pliss tolongg ​

Answer 1

Jawaban:

165

Penjelasan dengan langkah-langkah:

U3 = 24

a + (3-1)b = 24

a + (2)b = 24

a + 2b = 24....(1)

U6 = 15

a + (6-1)b = 15

a + (5)b = 15

a + 5b = 15...(2)

a + 2b = 24

a + 5b = 15

_________-

-3b = 9

b = 9/-3

b = -3

a + 2b = 24

a + 2(-3) = 24

a - 6 = 24

a = 24 + 6

a = 30

Sn = n/2 (a + Un)

Sn = n/2 (a + (a + (n-1)b))

S10 = 10/2 (30 + (30 + (10-1)-3))

S10 = 5 (30 + (30 + (9)-3))

S10 = 5 (30 + (30 - 27)

S10 = 5 (30 + 3)

S10 = 5 (33)

S10 = 165