Where do I plug in the values

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kory

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I'm not quite sure where to plug in the listed values...
 

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kory said:
I'm not quite sure where to plug in the listed values...
Click to expand...
Do you know the formula for average velocity?

It's distance traveled divided by time.

Let's take the first case, the interval [1, 2]. That means from t=1 to t=2. Plug those values into the given function to find the rock's height y at each time. The distance it's traveled in that time is the difference of the two values of y. So divide that difference by the elapsed time, 2 - 1 = 1 second. That will give you the velocity they are asking for.

The formula can also be written as [MATH]v=\frac{y_2-y_1}{t_2-t_1}=\frac{f(t_2)-f(t_1)}{t_2-t_1}[/MATH].
 
The answer for (i) is 4.42....How is 2-1 / 2-1 = 4.42??
 
kory said:
The answer for (i) is 4.42....How is 2-1 / 2-1 = 4.42??
Click to expand...

How do you get that???

For [MATH]t=2[/MATH], [MATH]y=10(2)-1.86(2)^2=12.56[/MATH], not 2.

I said to plug into the given function (to find y); you don't seem to have touched it.
 
1st of all, 2-1 / 2-1 = 2 -1/2 -1 = 1/2.
If you mean (2-1)/(2-1), then write that.
f(2) is not 2 and f(1) is not 1. If that was true, then the formula that Dr Peterson gave you would always be 1.
f(2) = 10(2)-1.86(2)2 = 20-7.44= 12.56, NOT 2
 
Oh ok...I got 12.56 too but I saw another example that had 4.42 as an answer. That was driving me crazy lol
 
kory said:
Oh ok...I got 12.56 too but I saw another example that had 4.42 as an answer. That was driving me crazy lol
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Did you think I would do the whole thing for you???

You also have to calculate f(1), and then put that into the formula. Yes, the answer will be 4.42, but you won't get it if you don't do the work.
 
Usually when I start a new topic, I watch a few videos to try to understand the logic from different perspectives. Sometimes people will explain things in a way that I can see more clearly. If I still feel lost, then I come here for help. I saw an answer that didnt align with 12.56 so I wasn't sure what to do.
 
kory said:
Usually when I start a new topic, I watch a few videos to try to understand the logic from different perspectives. Sometimes people will explain things in a way that I can see more clearly. If I still feel lost, then I come here for help. I saw an answer that didnt align with 12.56 so I wasn't sure what to do.
Click to expand...

I am not understanding you. The answer (average velocity) is 4.42, not 12.56. The latter is the value of f(2), which is just one part of the work.

Are you saying that you think that the answer should be 12.56, or that the site you found showed something other than 12.56 for f(2)?
 
Ok....for (i)
When I plug the number [1,2] I get 12.56
You are saying the answer is 4.42.
How do I get to 4.42 ???

My professor gave me some practice examples so im just trying to figure out what i'm looking at. This is not for a grade.
 
kory said:
I uploaded an image of the problem. Thats all I got. (i) says plug in [1,2]....Not sure what else to do....
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Please give us the definition of "Average velocity " from your textbook!
 
kory said:
Ok....for (i)
When I plug the number [1,2] I get 12.56
You are saying the answer is 4.42.
How do I get to 4.42 ???

My professor gave me some practice examples so im just trying to figure out what i'm looking at. This is not for a grade.
Click to expand...
Perhaps you don't understand that the notation [1,2] means the INTERVAL from 1 to 2, though I told you that in post #2. It is not a single number, and the comma is not a decimal. See https://www.mathsisfun.com/sets/intervals.html

So you have to find both f(1) and f(2), and put them into the formula. It appears that you have not year found f(1).
 
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