00:01
Okay, let's review the context real quick.
00:02
This function c represents the cost of producing x units.
00:08
And then this function, x of t, is how many number of units produced in t hours.
00:14
So first, finding c of x of t.
00:19
This is just a composition function.
00:21
I'm just plugging in x of t in for my x values of c.
00:26
So i'm replacing all of x of t, 50t, with x times 50t plus 750.
00:34
I could simplify a little bit more.
00:36
60 times 50 is going to be 3 ,000 t plus 750.
00:41
So what this function represents, this is the cost, remember, the weekly costs after t hours have been worked.
00:51
So i ignore the x at this point.
00:52
I'm just looking at what's the units of c.
00:54
The weekly costs after t hours have been worked.
01:00
Okay, from this, now i can use this to find the cost of producing units in four hours.
01:06
I could just plug in four into this function.
01:12
What would i do first? always multiply before i add or subtract plus 750, 12 ,000 plus 750 will be 12 ,750 750 units, or excuse me, this is cost.
01:30
It will cost $12 ,750 after four hours of work, which a lot of cost...