00:01
Hi there, so for this problem, we are given the expression for the volume of this, that is pi times the radius square times the height.
00:07
Now remember that the radius is given and that radius is 8.
00:12
So the expression for the volume in this now becomes just simply, well, we substitute the radius in here that is to the square, so we obtain 64 times pi times the height.
00:25
Now we already know that the rate of change of the volume with respect to time is equal.
00:30
To 64 times pi times the rate of change of the height with respect to time, okay? now, for part three of this problem, we are told that the rate that the height of water in the tan is increasing is a function of the height of the water in the tan and can be modeled by the following function.
00:52
And that is the function that we're going to label as x of h.
00:56
And then this is equal to 4 times the espionionion of 3 minus h and this plus 1.
01:06
Now, if you read the statement for this problem, you can see that this expression corresponds to the rate that the height of water in the 10 is increasing.
01:17
So this is precisely the rate of change of the height with respect to time.
01:22
So what we need to do is to substitute that expression in here.
01:26
But first of all, we need to determine the value of the height.
01:29
That as i can see, you already obtained because we just set the volume that we are given for this case, which is 192 times pi.
01:39
We set this to the expression of 64 times pi times the height...