Suku ke 50 barisan aritmetika 42,45,48,51,54

Barisan Aritmatika

U1 = a = 42
U2 = a + b = 45

b = U2 – U1
b = 45 – 42
b = 3

Un = a + (n–1)b
U50 = a + (50–1)b
U50 = 42 + (49 × 3)
U50 = 42 + 147
U50 = 189