驻波是一种特殊的干涉现象,不光有横驻波,也有纵驻波。
查看答案
采用龙格-库塔法求解常微分方程的初值问题时,公式阶数越高,数值解越精确。
A. 对
B. 错
只要函数f(x,y)适当光滑连续,则常微分方程的初值问题必有唯一解。
A. 对
B. 错
在中国,中秋节是一个全家团圆的节日。按照中国的农历每年的8月15月圆的那天就是中秋节。The Mid-Autumn Festival,Zhongqijie is a festival for families to ____ in China. It falls on the 15th day of the 8th lunar month,when the full moon returns to the sky.
这一天,人们喜欢吃一种圆形的点心,像月亮一样叫做月饼。再配上新鲜的水果,一家人围坐一起欣赏天上又亮又圆的满月。On this day, people eat a moon-shaped ____ called a ____. All the family members sit together, eat Moon Cakes and fresh fruits, and enjoy the sight of the round and bright moon.