18.有一數列為
【用戶】aabb177
【年級】國一上
【評論內容】P4 =1 = 4P3-3P2 = 52☆1-12☆1=40☆1☆3=4...
【用戶】Liao Ping Lun
【年級】高三上
【評論內容】因為P0= 0,所以 P2 = 4P1 - 3P0 = 4P1 ==> 式(1)P3 = 4P2 - 3P1 = 4*4P1 - 3P1 = 13P1 ==> 式(2)P4 = 4P3 - 3P2 = 4*13P1 - 3*4P1 = 40P1 ==> 式(3)且 P4 = 1 = 40P1,所以 P1 = 1/40,帶入式(1)得到 P2 = 4/40