解题方法
1 . 某地区上年度电价为0.8元
,年用电量为
,本年度计划将电价下降到0.55元
至0.75元
之间,而用户期望电价为0.4元
.经测算,下调电价后新增用电量和实际电价与用户的期望电价的差成反比,且比例系数为
(注:若
与
成反比,且比例系数为
,则其关系表示为
).该地区的电力成本价为0.3元
.
(1)下调后的实际电价为
(单位:元
),写出新增用电量
关于
的函数解析式;
(2)写出本年度电价下调后电力部门的收益
(单位:元)关于实际电价
(单位:元
)的函数解析式;(注:收益=实际电量
(实际电价-成本价))
(3)设
,当电价最低定为多少时,仍可保证电力部门的收益比上年至少增长
?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c110c151b9da7bf4ab263c66e49da6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d98d43b4d4f7c618731a21e1a7d1153.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c110c151b9da7bf4ab263c66e49da6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c110c151b9da7bf4ab263c66e49da6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c110c151b9da7bf4ab263c66e49da6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84f5919d0a77f348e0973f148bc2dc17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c110c151b9da7bf4ab263c66e49da6c.png)
(1)下调后的实际电价为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c110c151b9da7bf4ab263c66e49da6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(2)写出本年度电价下调后电力部门的收益
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c110c151b9da7bf4ab263c66e49da6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2468403b3eba9e40bfa36f464e927738.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78f61eaee66b6f9128db1088ec3af55a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8ee628efd6b2f7296c106dd5cbae42f.png)
您最近一年使用:0次