Suku ke14 barisan 15,24,35,48,63 adalah A 185 B 194 C288 D 312

15, 24, 35, 48, 63 -> a + b + c
9 11 13 15 -> 3a + b
2 2 2 -> 2a

2a = 2
a = 1

3a + b = 9
3(1) + b = 9
b = 9 – 3
b = 6

a + b + c = 15
1 + 6 + c = 15
c = 15 – 7
c = 8

Un = an^2 + bn + c
U14 = 1(14^2) + 6(14) + 8
U14 = 196 + 84 + 8
U14 = 288

jawaban = c