【正文】 的通積分為 Cyyxxy yx ?? ??0 20 dd2 （ 4 分） 計算得 Cyyx ?? 32 31 （ 6 分） 15． 解 ： 原方程是克萊洛方程，通解為 32CCxy ?? （ 6 分） 四、計算題 （每小題 10 分，本題共 20 分） 16． 解 ： 對應齊次方程的特征方程為 052 ?? ?? ， （ 1 分） 特征根為 01?? ， 52?? ， （ 2 分） 3 齊次方程的通解為 xCCy 521 e?? （ 4 分） 因為 0?? 是特征根。s public security bureau shows some 100 foreign visitors enjoyed the 72hour policy by the end of March, most of them from the United States, the United Kingdom and Germany. Chengdu also reported robust growth in its overall tourist industry last year. Official statistics show that it received some 150 million tourists last year, an increase of 28 percent from 2021. Around million came from abroad, an increase of 12 p ercent. Total revenue from tourism surpassed 133 billion yuan ($). During his visit to Kazakhstan in September, Chinese President Xi Jinping proposed that China and Central Asia join hands to build a Silk Road economic belt to boost cooperation. The idea has been widely echoed in Central Asian countries, being an encouraging blueprint for Chinese areas along the Silk Road that has linked Asia and Europe for more than 2,000 years. In the next three weeks, China Daily reporters will travel through the belt in China and in Kazakhstan, Uzbekistan and Turkey. They will show the progress and expectations of the countries, businesses and peoples on the route. Shaanxi the start of the ancient Silk Road has positioned itself as the new starting point for the development of the Silk Road Economic Belt, which will strengthen China39。s business development. Rudy Buttignol, president of the public broadcasting pany in British Columbia, Canada, said his work requires frequent travel to Chengdu and the policy makes the trips easier. Data from the city39。 1 常微分方程模擬試題 一、 填空題（每小題 3 分，本題共 15 分） 1．一階微分方程的通解的圖像是 2 維空間上的一族曲線．