dcc + differential equations = atrocious

[Mao]

yep

[18:43]   <dcc>   ok
[18:44]   there is 250 litres of liquid in a tank, and 30 grams of salt (initially)
[18:44]   <dcc>   A solution is being pumped in at 9 L/min with a concentration of x g/L
[18:44]   The solution is kept uniform by mixing and is pumped out at a rate of 13L/min
[18:44]   Find Q, the amount of salt in the tank at time T
[18:45]   assume x consant

differential equation:

equation A:



let





then solve for C using initial condition = VERY UGLY solution

[dcc]

(18:43:49) (dcc) there is 250 litres of liquid in a tank, and 30 grams of salt (initially)
(18:43:58) (Mao) dcc: is that the hardest?
(18:44:05) (dcc) A solution is being pumped in at 9 L/min with a concentration of x g/L
(18:44:19) (dcc) The solution is kept uniform by mixing and is pumped out at a rate of 13L/min
(18:44:31) (dcc) Find Q, the amount of salt in the tank at time T
(18:45:14) (dcc) assume x constant

[dcc]

lol

[AppleXY]

(Image removed from quote.)

holy sweet mother.

[Ahmad]

http://en.wikipedia.org/wiki/Linear_differential_equation#First_order_equation

[Mao]

lol

MATHEMATICA EXPOSED!!!!!

[dusty_girl1144]

wow. took me 3 days to do differntial equations... for just one exercise. i feel so stupid

[midas_touch]

I don't think youse will be required to solve these types of DEs in Spesh, you'll only have to be able to set them up afaik.

[bigtick]

Note:
Is dt/dQ = f(Q) + constant  the same as dQ/dt = 1/f(Q) + constant ?
Is the same as ?

[beezy4eva]

i told you dcc is evil

[AppleXY]

i told you dcc is evil

lol why is dcc evil. Is it because he's smarter than u

[beezy4eva]

i told you dcc is evil

lol why is dcc evil. Is it because he's smarter than u

partially
also coz he keeps making poor mayo do long questions

[Mao]

Note:
Is dt/dQ = f(Q) + constant  the same as dQ/dt = 1/f(Q) + constant ?

did you mean or ?

the earlier would be true [even though some "real" mathematicians are against it], the latter will be false.

please learn how to use


[and oh, i see what you mean now... yes, that's a big mistake =P ]

[phagist_]

Note:
Is dt/dQ = f(Q) + constant  the same as dQ/dt = 1/f(Q) + constant ?

It would be the same if it wasn't an initial value problem (i.e you didnt' have to find the constant), since c represents ANY arbitrary constant.

I THINK.

[dusty_girl1144]

so what IS an easy way to determine how to put together a differential equation. because this has been the worst topic for me... i dunno where to start!!!