00:01
In this question, the revenue function rx equals to 50x minus 0 .5x square and the cost function cx equals to 2x plus 10 when x equals to 35 and dx upon dt equals to 25 units per day.
00:23
So rate of change of total revenue is given by d by dt of rx.
00:39
So this is equals to r dr by dt.
00:45
Dr by dt equals to 50 dx upon dt minus 0 .5 into 2x into dx upon dt.
00:57
So rate of change of total revenue will be 50 into dx upon dt is 25 minus this value will be 0 .1 .0 and into x so here x is 35 and dx upon dt is 25.
01:16
So taking 25 common this will be 50 minus 35.
01:22
So this is equals to 25 multiplied by 15.
01:27
So on multiplexing equals to $3 .75.
01:32
Now the next one rate of change of total cost.
01:37
So rate of change of total cost, total cost that is given by c dash x equals to c dash x equals to 2 times of dx upon dt and plus derivative of constant term is 0.
01:59
So this is equals to 2 into dx upon dt is 25.
02:04
So rate of change of cost...