4.9 项目:指数和对数函数
章节大纲
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Hurricane Fran hit North Carolina on the evening of September 5, 1996. Over 1 million homes and businesses were left without power. Repair crews began immediately restoring electrical service. The following table lists the number of customers without power:
::弗朗飓风在1996年9月5日晚上袭击北卡罗来纳州,100多万家庭和企业停电,修理人员立即开始恢复电力服务。Date Customers without power September 6 1,159,000 September 7 804,000 September 8 515,000 September 9 340,000 September 10 195,200 September 11 136,300 September 12 77,000 September 13 37,600 -
Use graph paper to plot the data points, using a clear scale. Sketch a best guess at an appropriate model. Several points may be off the curve, so just try to balance the number above and below the curve.
::使用图形纸绘制数据点, 使用清晰的尺度 。 在合适的模型中绘制最好的猜测 。 几个点可能离曲线不远, 所以尽量平衡曲线上和下的数字 。 -
What kind of function seems to fit this curve?
::什么样的功能似乎适合这个曲线? -
What would the equation of the parent function (model) be?
::母函数(模型)的等式是什么? -
Pick two points that are on the sketched curve, and come up with a specific function that fits it.
::选择在草图曲线上的两点, 并得出一个适合它的具体函数 。 -
Choose a point that is not on the sketched curve. Calculate its value predicted by the model. What is the percentage error between the predicted and the actual value?
::选择一个不在草图曲线上的点。 计算模型预测的值。 预测值和实际值之间的百分比错误是多少? -
Is it appropriate to discuss half-life or doubling time with this data? Explain. Then find the value of the appropriate one.
::与这些数据讨论半衰期或翻倍时间是否合适? 请解释 。 然后找到合适的值 。 -
If the recovery continued at the same pace, how long until all power was restored (less than 1,000 customers without power)?
::如果恢复继续以同样的速度进行,恢复所有电力(少于1 000个没有电力的客户)还要多久? -
Find the function whose domain is number of customers without power and range is the date when that power is restored. What is its relationship to the function created in question 4?
::查找一个函数, 其域是没有电力的客户数量, 范围是恢复该权力的日期。 它与问题 4 中创建的函数有什么关系 ?
Reference:
::参考:"Hurricane Fran: September 5, 1996." Hurricane Fran: September 5, 1996 . National Weather Service, n.d. Web. 01 Apr. 2016.
::“飓风弗朗:1996年9月5日” 飓风弗朗:1996年9月5日,国家气象局,网址:Web. 2016年4月1日。 -
Use graph paper to plot the data points, using a clear scale. Sketch a best guess at an appropriate model. Several points may be off the curve, so just try to balance the number above and below the curve.