详细信息: 输入的方程组为:
| | | | 10 | A | + | | 300 | B | + | | 520 | C | + | | 888 | D | + | | 52 | E | + | | 2288 | F | + | | 20 | G | + | | 4888 | H | = | | 100 | | (1) |
| | A | + | | B | + | | C | + | | D | + | | E | + | | F | + | | G | + | | H | = | | 1 | | (2) |
| | | | | | | 解题过程:
将第 (1) 等式两边 除以10后,可以得到等式: | | A | + | | 30 | B | + | | 52 | C | + | | | 444 5 | D | + | | | 26 5 | E | + | | | 1144 5 | F | + | | 2 | G | + | | | 2444 5 | H | = | | 10 | (9) | ,然后再同时用第 (2) 等式两边 减去 等式(9)两边,方程组化为:
| | | | 10 | A | + | | 300 | B | + | | 520 | C | + | | 888 | D | + | | 52 | E | + | | 2288 | F | + | | 20 | G | + | | 4888 | H | = | | 100 | | (1) |
| -29 | B | | -51 | C | | - | 439 5 | D | | - | 21 5 | E | | - | 1139 5 | F | | -1 | G | | - | 2439 5 | H | = | | -9 | | (2) |
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将第 (2) 等式两边 乘以300 除以29后,可以得到等式: | -300 | B | | - | 15300 29 | C | | - | 26340 29 | D | | - | 1260 29 | E | | - | 68340 29 | F | | - | 300 29 | G | | - | 146340 29 | H | = | | - | 2700 29 | (10) | ,然后再同时用第 (1) 等式两边 加上 等式(10)两边,方程组化为:
| | | | 10 | A | | - | 220 29 | C | | - | 588 29 | D | + | | | 248 29 | E | | - | 1988 29 | F | + | | | 280 29 | G | | - | 4588 29 | H | = | | | 200 29 | | (1) |
| -29 | B | | -51 | C | | - | 439 5 | D | | - | 21 5 | E | | - | 1139 5 | F | | -1 | G | | - | 2439 5 | H | = | | -9 | | (2) |
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将未知数的系数化为1,方程组化为:
| | | | A | | - | 22 29 | C | | - | 294 145 | D | + | | | 124 145 | E | | - | 994 145 | F | + | | | 28 29 | G | | - | 2294 145 | H | = | | | 20 29 | | (1) |
| | B | + | | | 51 29 | C | + | | | 439 145 | D | + | | | 21 145 | E | + | | | 1139 145 | F | + | | | 1 29 | G | + | | | 2439 145 | H | = | | | 9 29 | | (2) |
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所以,方程组的解为:
| | | A = | | | 20 29 | + | | | 22 29 | C | + | | | 294 145 | D | - | | | 124 145 | E | + | | | 994 145 | F | - | | | 28 29 | G | + | | | 2294 145 | H |
| B = | | | 9 29 | - | | | 51 29 | C | - | | | 439 145 | D | - | | | 21 145 | E | - | | | 1139 145 | F | - | | | 1 29 | G | - | | | 2439 145 | H |
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将方程组的解化为小数:
| | | A = | | 0.689655 | + | | | 22 29 | C | + | | | 294 145 | D | - | | | 124 145 | E | + | | | 994 145 | F | - | | | 28 29 | G | + | | | 2294 145 | H |
| B = | | 0.310345 | - | | | 51 29 | C | - | | | 439 145 | D | - | | | 21 145 | E | - | | | 1139 145 | F | - | | | 1 29 | G | - | | | 2439 145 | H |
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其中: C, D, E, F, G, H 为任意常数。 解方程组的详细方法请参阅:《多元一次方程组的解法》 |