题库搜索>问题求解PS-13315
According to a certain estimate, the depth N(t), in centimeters, of the water in a certain tank at t hours past 2:00 in the morning is given by N(t) = -20(t−5)2 + 500 for 0 ≤ t ≤ 10. According to this estimate, at what time in the morning does the depth of the water in the tank reach its maximum?
分析A选项
分析B选项
分析C选项
分析D选项
分析E选项
我有更好的解析 
暂无雷哥网文字解析
要使N（t）的值最大，t=5，而t是从2点以后算的，我们那时候应该是7点
科目：
问题求解PS
来源：
GWD
题目信息1m20s
平均耗时
90.4%
平均正确率
该题由网友puMmphts提供
点击上传问题求解PS -17850
A certain brand of house paint must be purchased either in quarts at $12 each or in gallons at $18 each. A painter needs a 3-gallon mixture of the paint consisting of 3 parts blue and 2 parts white. What is the least amoumt of money needed to purchase sufficient quantities of the two colors to make ...
问题求解PS -17819
If 2x+ 5y=8 and 3x=2y, what is the value of 2x+y ?
问题求解PS -17817
If st =2, then the value of which of the following can be determined ?Ⅰ.2ts Ⅱ.s−tt Ⅲ.t−1s−1
问题求解PS -17813
The sum of the ages of Doris and Fred is y years. If Doris is 12 years older than Fred, how many years old will Fred be y years from now,in terms of y ?
问题求解PS -17811
If k≠0 and ,then x=
问题求解PS -17850
A certain brand of house paint must be purchased either in quarts at $12 each or in gallons at $18 each. A painter needs a 3-gallon mixture of the paint consisting of 3 parts blue and 2 parts white. What is the least amoumt of money needed to purchase sufficient quantities of the two colors to make ...
问题求解PS -17819
If 2x+ 5y=8 and 3x=2y, what is the value of 2x+y ?
问题求解PS -17817
If st =2, then the value of which of the following can be determined ?Ⅰ.2ts Ⅱ.s−tt Ⅲ.t−1s−1
问题求解PS -17813
The sum of the ages of Doris and Fred is y years. If Doris is 12 years older than Fred, how many years old will Fred be y years from now,in terms of y ?
问题求解PS -17811
If k≠0 and ,then x=
分享
周末、晚班滚动开班 
24+35+35+6课时 
