The profit from the production of type B masks is _ _ _ _ 0.3 (5-x) =1.5-0.3x _ _ _ _ _ _ ten thousand yuan.
(2)y = 0.5x+ 1.5-0.3x = 0.2x+ 1.5
Since the number of type A masks should not be less than 1.8, X >: = 1.8.
According to the production capacity of this factory, (x/0.6)+[(5-x)/0.8]
Therefore, the range of the independent variable x is 1.8.
(3)y=0.2x+ 1.5 is increasing function, and Y increases with the increase of X, so when the profit is maximum, X is substituted with the maximum value of x=4.2.
Y=0.2x+ 1.5, and the result is Y = 23400.
To finish the task in the shortest time, let t = (x/0.6)+[(5-x)/0.8] = (5/12) x+25/4 take the minimum value. This function is
In the incremental function, when the minimum value of x is 1.8, the minimum value of t =7 days. At this time, 18000 A-type masks and 32000 B-type masks were produced.