bisa bantu nomor 9 yaa?

[tex]3 , 9 , 18 , 30 , ...\\\\Dik :\\Suku Pertama = 3\\Beda = 6\\Beda Tetap = 3\\\\Jawab :\\2A = BedaTetap\\2A = 3\\A = \frac{3}{2} \\\\3A + B = Beda\\3( \frac{3}{2}) + B = 6\\B = 6 - \frac{9}{2}\\B = \frac{3}{2}\\\\A + B + C = SukuPertama\\ \frac{3}{2} + \frac{3}{2} + C = 3\\\frac{6}{2} + C = 3\\C = 3 - 3\\C = 0\\\\Fungsi Kuadrat \left[\begin{array}{ccc}Un = An^2 + Bn + C\end{array}\right]\\Un = \frac{3}{2}n^2 + \frac{3}{2}n\\U10 = \frac{3}{2}(10)^2 + \frac{3}{2}(10)\\U10 = 150 + 15\\U10 = 165[/tex]


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Matematika IX SMP
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Pembahasan :
3 , 9 , 18 , 30 , ...
..(+6)..(+9)..(+12)...

Pola bertambah +3

Maka...
3 , 9 , 18 , 30 , 45 , 63 , 84 , 108 , 135 , [165]

Opsi A.