This is a sub-page of a longer article, The classical Chinese version of Horner’s method: Technical considerations.
This sample is taken from available translations of the texts. The root given in the text is shown in boldface.
Section references are to the translation by Lim & Wagner (2017).
Section |
Equation |
Real roots |
3.2.3.1 |
x3 + 170x2 + 7,1662/3 x = 1,677,6662/3 |
70 |
3.2.3.2 |
x3 + 1,620x2 + 850,500x = 146,802,375 |
135 |
3.2.3.4 |
x3 + 276x2 + 19,184x = 633,216 |
24 |
3.2.3.5 |
x3 + 840x2 = 4,459,000 |
–833.58 |
3.3.3.2 |
x3 + 5,004 x2 + 1,169,9531/3 x |
–4,756.20 |
3.3.3.3 |
x3 + 3,2982/31 x2 + 2,474,94129/31 x |
1,920 |
3.4.3 |
x3 +62x2 + 696x = 38,448 |
18 |
3.4.4.2 |
x3 + 594x2 = 682,803 |
–592.05 |
3.4.4.3 |
x3 + 693x2 + 42,471x = 683,665.488 |
–623.08 |
3.5.3.2 |
x3 + 1,728x2 + 746,496x = 7,644,119,040 |
1,440 |
3.6.3 |
x3 + 135x2 + 4,550x = 285,000 |
30 |
3.6.4 |
x3 + 315x2 + 32,400x = 435,888 |
12 |
3.7.3.1 |
x3 + 15x2 + 66x = 360 |
3 |
3.7.3.2.3 |
x3 + 18x2 + 108x = 1,512 |
6 |
3.8.3 |
x3+ 90x2 = 839,808 |
72 |
3.9.3 |
x3 + 30x2 + 264x = 20,304 |
18 |
3.9.4 |
x3 + 162x2 + 8,748x = 215,784 |
18 |
3.10.3 |
x3 + 60.392 x2 + 911.998x = 32,369.022 |
15.5 |
3.11.3 |
x3 + 17 37/89 x2 + 99 14/89 x = 6,42927/89 |
13 |
3.12.3 |
x3 + 6.8x2 + 15.2x = 4,289.6 |
14 |
3.13.3 |
x3 + 35x2 + 441x = 5,145 |
7 |
3.14.3 |
x3 + 35x2 + 441x = 5,145 |
7 |
3.15 |
x3 + 189/20 x2 = 6,754129/500 |
147/20 |
3.16 |
x3 + 31/10 x = 1,313,7831/10 |
1081/2 |
3.17 |
x3 + 23/4 x2 + 2/50 x = 812,59159/125 |
922/5 |
Libbrecht (1973: 209–211) gives a list of the equations solved in this book. It uses fractional approximations instead of decimals; in these cases I give the approximation, its value using decimals, and the correct root.
Equation |
Roots |
x2 + 82,655x – 2,269,810,000 = 0 * |
-104,397.0827 |
x2 + 2x – 399 = 0 |
–21 |
9x2 + 5,100x – 322,500 = 0 |
–624.0841 |
528,381x2 + 360,099,600x –18,933,652,500 = 0 |
–730.5639 |
16x2 + 192x – 1,863.2 = 0 |
–18.3471 |
36x2 + 360x – 13,068.8 = 0 |
–24.6983 |
0.5x2 – 152x –11,552 = 0 |
–62.9605 |
6x2 + 234x –2,600 = 0 |
–48.0234 |
–x4 + 763,200x2 – 40,642,560,000 = 0 |
–840 |
–x4 + 15,245x2 – 6,262,506.25 = 0 |
–121.7477, |
–x4 + 1,534,464x2 – 526,727,577,600 = 0 |
–1008 |
x10 +15x8 + 72x6 – 864x4 –11,664x2 – 34,992 = 0 |
–3 |
* On this text see ‘Qin Jiushao’s curious formula for the area of a banana leaf’.
These are the equations from this book which are treated by Chemla (1982). The left column gives the Problem number in the volume ‘Appendice III’.
|
Equation |
Roots |
III-9 |
–2x2 + 28,800 = 0 |
120 |
III-13 |
x4 – 654x3 + 106,929x2 + 22,472,640x |
–152 |
V-12 |
0.5x3 –1,200x2 +427,200x –40,320,000 = 0 |
168.7371 |
V-13 |
2x4 –1,200x3 +319,200x2 +36,720,000x |
–153.5510 |
V-13 |
0.5x4 –600x3 +319,200x2 –240,480,000x +64,800,000,000 = 0 |
360 |
V-14 |
–4x3 + 3600x2 –1,256,400x + 105,840000 = 0 |
120 |
V-14 |
–0.5x3 –88,200x – 55,080,000 = 0 |
360 |
VI-18 |
4x3 –1,280x2 + 270,080x – 20,889,600 = 0 |
120 |
VI-18 |
–0.5x3 + 320x2 –135,040x + 20,889,600 = 0 |
240 |
VII-1 |
–x2 + 204x + 8,640 = 0 |
–36, |
VII-1 |
–x2 + 102x + 2,160 = 0 |
–18 |
VII-1 |
–2x2 + 204x + 4,320 = 0 |
–18 |
VII-1 |
x2 – 19,044 = 0 |
–138 |
VII-2 |
–2160x4 + 444,960x3 – 10,628,820,000x + 717,445,350,000 = 0 |
–143.7799 |
VII-2 |
–x4 +8,640x2 + 652,320x + 4,665,600 = 0 |
–7.9921 |
VII-2 |
–2x4 + 604x3 + 17,280x2 – 8,553,244x + 401,067,842 = 0 |
–127.2601 |
VII-2 |
–2x6 –714x5 –62,165x4 – 2,220,302x3 + 82,926,816x2 |
–254.2681 |
VIII-15 |
–70.4375x2 –6,198.5x + 25,921 = 0 |
–92 |
XI-18 |
–x4 –1,406x3 –511,907x2 –4,730,640x |
120 |
XII-1 |
16x2 –328,960x + 26,214,400 = 0 |
80 |
XII-7 |
–289x2 + 462,400 = 0 |
–40 |
XII-9 |
–0.5x2 –680x + 192,000 = 0 |
–1,600 |
These are taken from Lam Lay Yong (1977).
Page |
Equation |
Roots |
71, 146 |
-3x2 + 228x - 4,320 = 0 |
36 |
72, 146 |
-x2 + 312x - 6,912 = 0 |
24 |
72, 146 |
-8x2 + 312x - 864 = 0 |
3 |
73, 147 |
7x2 - 9072 = 0 |
–36 |
74, 147 |
x2 + 200x - 8,225 = 0 |
–235 |
75, 147 |
6x2 + 48x - 390 = 0 |
–13 |
75, 144 |
-5x4 + 52x3+ 128x2 - 4,096 = 0 |
4 |
75–76, 147 |
-x2 + 36x - 180 = 0 |
6 |
76, 147 |
4x2 - 144 = 0 |
–6 |
In the conversion of ecliptic to equatorial coordinates by a proto-trigonometric method this system uses an approximation for the sagitta of an arc given the diameter and the length of the arc:
s4 + (d2–ad)s2 – d3s + d2a2/4 ≈ 0
where
d = diameter
a = length of arc
s = sagitta
The system uses this approximation with d = 121.75 and 0 < a < 91.3125. In this range the equation has two roots, shown here:
The correct root is the smaller of the two.
These are taken from Guo Shuchun et al. (2006).
Page |
Equation |
Roots |
42, 43, 47, 48 |
x5 – 9x4 – 81x3 +729x2 –3,888 = 0 |
-8.8439 |
50, 53, 55 |
x2 – 2x – 8 = 0 |
-2 |
66, 69 |
x4 – 6x3 + 4x2 + 6x –5 = 0 |
-1 |
84, 85 |
4x2 – 7x – 686 = 0 |
-12.25 |
86, 87 |
181x8 – 22,868x6+ 278,926x4 – 818,100x2 + 253,125 = 0 |
-10.6332 |
88, 89 |
–x8 – 70x6 + 6,479x4 – 186,624x2 + 1,679,616 = 0 |
-4 |
90, 91 |
x4 – 12x3 – 54x2 + 140x + 1,525 = 0 |
5 |
90 |
–x3 + 2x2 + 100x – 200 = 0 |
-10 |
92, 93 |
–9x3 + 59x2 – 123x + 8,532 = 0 |
12 |
94, 95 |
27x3 – 600x2 + 3325x – 130,000 = 0 |
25 |
94, 95 |
4x3 – 51x2 + 132x – 29,088 = 0 |
24 |
96, 97 |
100x4 – 3,960x3 + 39,204x2 – 81x – 944,055 = 0 |
-4.0698 |
98, 99 |
–x2 + 200x – 4,071 = 0 |
23 |
98 |
x4 – 4x3 – 4,249x2 + 4,494,400 = 0 |
40 |
100, 101 |
x2 – 36x + 315 =0 |
15 |
102, 103 |
5x4 – 3x3 – 12x2 – 9x – 503,334 |
-17.6960 |
102, 103 |
x6 – 2x2 –x – 46,578 = 0 |
-5.9997 |
104, 105 |
x6 + 18x5 + 99x4 + 162x3 + 74x2 – 9x – 155,805 = 0 |
-11.3018 |
106, 107 |
x6 – 4x5 + 14x4 – 20x3 + 26x2 – 5x – 78,414 = 0 |
-5.7099 |
108 |
x5 – 28x4 + 295x3 – 1,386x2 + 2,450x – 7,800 = 0 |
12 |
108, 109 |
18x9 – 6x8 + 72x6 +x4 –9x2 – 12268 = 0 |
2 |
110, 111 |
16x10 – 64x9 + 160x8 – 384x7+ 512x6 – 544x5 + 465x4 + 126x3 + 3x2 –4x – 177,162 = 0 |
-1.9728 |
112, 113 |
x4 – 30x3 + 499x2 – 5,320x + 22,178 = 0 |
8.2898 |
114, 115 |
5x3 – 13x2 – 5x – 13,875 = 0 |
15 |
x4 – 26x3 – 467x2 + 8,300x + 97,440 = 0 |
-14.1047 |
|
118, 119 |
x3 + 3x2 – 50x – 4,064 = 0 |
16 |
120, 121 |
x2 – 17x – 200 = 0 |
-8 |
122, 123 |
x4 – 17x3 + 98x2 – 255x + 189 = 0 |
1.1638 |
124, 125 |
–49x6 – 495x5 + 5,371.75x4 + 278,768x3 + 843,296x2 – 7,023,616x – 133,448,704 = 0 |
8 |
126, 127, 129 |
5x4 + 19x2 – 106,416 = 0 |
-12 |
129, 130, 131 |
21x7 + 40x6 – 277x5 – 425x4 + 908x3 + 1,009x2 + 236x – 190,656 = 0 |
4 |
132, 133 |
–x4 + 2,046x2 + 2,520x – 447,525 = 0 |
-41.5460 |
134, 135 |
9x4 – 48x3 + 80x2 – 115,200 = 0 |
-9.3543 |
136, 137 |
3x3 – 321x2 + 4,072x + 12,816 = 0 |
-2.6011 |
|
3x3 – 231x2 + 4,072x + 12,816 = 0 |
-2.7146 |
138, 139 |
–x4 + 74x3 – 214x2 + 420x – 33,831 = 0 |
9 |
140, 141 |
11x2 – 12x – 128 = 0 |
-2.9091 |
142, 143 |
2x3 + 2x2 –27x – 11,826 = 0 |
18 |