Simpsons rule question (1 Viewer)

[PC]

Nah ... you can't do this with Simpson's Rule.

I would say that there is a bit missing from the original diagram. Perhaps the curve drops away at the left, and there's the extra 12 on the bottom left.

So A = 12/3 [0 + 4 x 8 + 10] + 12/3 [10 + 4 x 19 + 40]
= 672 m²

Smithyo's answer is the other alternative, but it's less likely for the curve to drop away at the right. Possible though.

 

[rebbii.rooty]

I'm pretty sure this is the answer:

Sorry if its not the best photo!

 

[UNZPME]

I'm pretty sure this is the answer:

Sorry if its not the best photo!

yh that is the anserrr

 

[PC]

No ... because you're counting the middle section twice.

 

[zzdfa]

http://img293.imageshack.us/my.php?image=sdfsdfck5.jpg

find area from 0 to 24, A1
find area from 12 to 36, A2
find area from 12 to 24 in terms of f(18), M
now you have an eqn:

total area = A1 + A2 - M

now find area from 0 to 36 directly using 1 application of simpson's rule
solve the simultaneous equations for f(18) and plug it in to get area

and you get 316.5


is this correct?


btw i don't get why you are arguing about how it has to drop to zero or something, are you saying that you need to have a zero to use simpsons rule (in which case my answer is wrong).

 

[Anita8888]

hey
this is what i worked out using the formula

12/3[(8+40)+(4x10)+(2x19)]

the answer ends up being 472

i hope thats right but i'm not sure

 

[zzdfa]

oops i really screwed up before, here is the corrected version:
http://img293.imageshack.us/my.php?image=simshr6.jpg

find area from 0 to 24, A1
find area from 12 to 36, A2
find area from 12 to 24 in terms of f(18), M
now you have an eqn:

total area = A1 + A2 - M

now find area from 0 to 36 directly using 1 application of simpson's rule
solve the simultaneous equations for A

and you get 607.5

is this correct?


btw i don't get why you are arguing about how it has to drop to zero or something, are you saying that you need to have a zero to use simpsons rule (in which case my answer is wrong).

 

[michael1990]

oops i really screwed up before, here is the corrected version:
http://img293.imageshack.us/my.php?image=simshr6.jpg

find area from 0 to 24, A1
find area from 12 to 36, A2
find area from 12 to 24 in terms of f(18), M
now you have an eqn:

total area = A1 + A2 - M

now find area from 0 to 36 directly using 1 application of simpson's rule
solve the simultaneous equations for A

and you get 607.5

is this correct?


btw i don't get why you are arguing about how it has to drop to zero or something, are you saying that you need to have a zero to use simpsons rule (in which case my answer is wrong).

I believe your answer is wrong anyway.
Because you have put a line down the middle, so that would change the distance on the horizontal.

 

[zzdfa]

change which distance?

 

[PC]

No, it's just that for this course, to use Simpson's rule, you need an even number of sections. Full stop.

I'm just saying that the original question has information missing.

 

[anurag1.2005]

u need to make sure that u find the hight ie 12 in dis question n then use the formula (f(a) + 4.0*f(c)+2*f(d) + f(b)) in this question F(a) is 8 ......and so on put in the Y coordinate values instead of the next ones respectively

 

[henry08]

Is Simpson's rule even General maths?

 

[ronakie]

yes it is in general maths

 

[songs4thesadman]

um. it only said write a formula didn't it?
that means you don't have to solve it

unless we are talking about the second part to the question

 

[songs4thesadman]

i actually thought this was a really easy question. i don't understand why everyone had so much trouble with it