00:02
And so here is our expression for the position.
00:05
It's b times t squared minus c times t to the fourth.
00:10
And we're told that b is equal to 1 .82 meters per second squared.
00:15
So part a asks what value of c will give us back to x equals zero at time equals 2 .45 seconds.
00:27
So to find that, we just plug in and solve for c.
00:33
Under those conditions.
00:35
So i put x equals to zero and then solve this expression for c, and then i'll plug in the rest of the stuff.
00:44
So we add c t to the fourth to both sides.
00:48
We get c t to the fourth equals bt squared, divide both sides by t to the fourth, and you get c is equal to b over t squared, because t squared over t to the fourth cancels to t squared.
01:00
I'm a denominator.
01:01
Plug in the value for b, 1 .82, and the value for time, 2 .54, and you get a value of c that is equal to 0 .8 .282 meters per second to the fourth...