" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2024 KUDO.TIPS - All rights reserved.
Verified answer
Materi : Barisan dan deretPembahasan :
Aritmatika Tingkat 2
30 , 42 , 56 , 72 , 90 , ...
2A = Konstanta
2A = [(U3 - U2) - (U2 - U1)]
2A = [(56 - 42) - (42 - 30)]
2A = [14 - 12]
2A = 2
A = 1
3A + B = Beda
3A + B = U2 - U1
3(1) + B = 42 - 30
3 + B = 12
B = 9
A + B + C = Suku awal
1 + 9 + C = 30
C = 20
Ingat Fungsi Kuadrat Kelas VIII
f(x) = Ax² + Bx + C
Un = An² + Bn + C
Un = n² + 9n + 20
Un = (n + 5)(n + 4)
U25 = (25 + 5)(25 + 4)
U25 = (30)(29)
U25 = 870 ——» Suku ke-25