Question

Diberikan barisan aritmatika -8,-3,2,7,...,112 Banyaknya suku barisan tersebut adalah...​

Answer 1

Barisan aritmetika

[tex]un = a + (n - 1)b \\ 112 = - 8 + (n - 1)5 \\ 112 = - 8 + 5n - 5 \\ 112 = - 13 + 5n \\ 112 + 13 = 5n \\ 125 = 5n \\ \frac{125}{5} = n \\ n = 25[/tex]