About
Community
Bad Ideas
Drugs
Ego
Erotica
Fringe
Society
Technology
register | bbs | search | rss | faq | about
meet up | add to del.icio.us | digg it
Go Back   Community > Science > Mad Scientists
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Mad Scientists Science and Mathematics discussion-- theories, arguments, citations, proofs and pudding.

Reply
 
Thread Tools Display Modes
 #1 
Old 2008-10-03, 19:49
Gallows Gallows is offline
Regular
 
Default Riemann Sum/Integral question

Hey mad scientists, I got this problem wrong on my test:( and I was wondering how to answer it. I memorized the way my book describes to do Riemann sums, but I guess I didn't completely understand it. Any help will be greatly appreciated.


The table gives the values of speedometer readings of a braking car taken every three seconds. Express the integral as a limit of Riemann sum using the values at the right end points of the intervals. Do not evaluate the limit.

Table:
Speed(feet per second): | 73 | 63 | 54 | 37 | 22 | 9 | 0 |
Time of Reading in Seconds: | 10 | 13 | 16 | 19 | 22 | 25 | 28 |
 #2 
Old 2008-10-04, 20:20
SelfAdjoint SelfAdjoint is offline
Regular
 
Default Re: Riemann Sum/Integral question

You mean you're wanting an estimate, using a Riemann summation, of the distance travelled in that time? Multiply each number by three (since that's the length of each time interval) and add them together. That's it. The integral is the limit of this sum as the length of each interval tends to zero.
 #3 
Old 2008-10-04, 23:37
Gallows Gallows is offline
Regular
 
Default Re: Riemann Sum/Integral question

Quote:
Originally Posted by SelfAdjoint
You mean you're wanting an estimate, using a Riemann summation, of the distance travelled in that time? Multiply each number by three (since that's the length of each time interval) and add them together. That's it. The integral is the limit of this sum as the length of each interval tends to zero.


What I want is the Riemann summation written as a limit. I know the answer contains a Sigma and a limit as n approaches infinity. I really hate these bullshit pseudo-conceptual problems....
 #4 
Old 2008-10-05, 17:30
Regular
 
The Big Rock Candy Mountains
Default Re: Riemann Sum/Integral question

lim t->inf of t sigma k=9 f(k+3)*3

I think thats it. Its been a while and I was always a little shaky with sigma notation.
 #5 
Old 2008-10-05, 18:43
Gallows Gallows is offline
Regular
 
Default Re: Riemann Sum/Integral question

Quote:
Originally Posted by OneMestizo
lim t->inf of t sigma k=9 f(k+3)*3

I think thats it. Its been a while and I was always a little shaky with sigma notation.


Thanks alot. That looks right.

By the way, is your location referring to the "paradise" or is it referring to the awesome, mind-shattering children's movie?
http://ecx.images-amazon.com/images/I/51CZ600F5BL._SL500_AA240_.jpg
 #6 
Old 2008-10-05, 18:45
Regular
 
The Big Rock Candy Mountains
Default Re: Riemann Sum/Integral question

Thanks alot. That looks right.

By the way, is your location referring to the "paradise" or is it referring to the awesome, mind-shattering children's movie?
http://ecx.images-amazon.com/images/I/51CZ600F5BL._SL500_AA240_.jpg

Hobo paradise. Never heard of the movie.
 
To the best of our knowledge, the text on this page may be freely reproduced and distributed.
 

totse.com certificate signatures
 
 
About | Community | Bad Ideas | Drugs | Ego | Erotica | Fringe | Society | Technology
Hot Topics