Besar aritmatika:U7= 15cmU11= 35cmUn=?dibantu segera ya
Jawaban Terkonfirmasi
Bab Barisan dan Deret
Matematika SMP Kelas IX
aritmatika
b = (U11 – U7) / (11 – 7)
= (35 – 15) / 4
= 20/4
= 5
a = U7 – 6b
= 15 – 6 x 5
= 15 – 30
= -15
Un = a + (n – 1)b
= (-15) + (n – 1) x 5
= (-15) + 5n – 5
= 5n – 20