Carilah nilai p jika 5+7+9+….+(2p-1)=957


A = 5, b = 2, Sn = 957, Sn = n/2(2a + (n-1)b), 957 = n/2(2.5 + (n – 1)2), 957 = n/2(10 + 2n – 2), 957 = n/2(2n + 8), 957 = n\xb2 + 4n, n\xb2 + 4n – 957 = 0, (n – 29)(n + 33) = 0, n – 29 = 0 v n + 33 = 0, n = 29 v n = -33 (ambil positif), Un = a + (n-1)b, U_29 = 5 + (29 – 1)2, (2p – 1) = 5 + 56, 2p – 1 = 61, 2p = 61 + 1, 2p = 62, p = 31…. ok?,
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Nilai P = 5+7+9….+(2p-1) = 957, =5+7 = 12 + 800 , = 812 + (146-1), = 957