00:01
So for this problem we have the trajectory of a golf ball.
00:04
We know that it's hit on the top of a platform at a vertical height of three.
00:09
So at time equals zero, it's three, and then it reaches the maximum vertical height after a horizontal distance of 90.
00:19
So we know that our vertex is 90 in the x direction, and then we wanna find that y maximum.
00:29
And then, so if we have it of the form y equals a times x minus, or x plus h squared plus k, or x minus h squared plus k.
00:52
Well, we see that when x is equal to zero, we'll have this term squared, and then it gives us the resulting k value.
01:02
So we want to ensure that when x is equal to zero, and we have y equals a h squared plus k, that's equal to three.
01:12
Then if we took the derivative, so we have y prime, which is two a times x minus h...