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anonymous
 5 years ago
how would one solve the equation (dy/dt = 5y +sin(3t)) ?
anonymous
 5 years ago
how would one solve the equation (dy/dt = 5y +sin(3t)) ?

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bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0do u know what to use for them? integrating factors.... etc.. what's the topic?

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0i dont wanna look for the method...

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0okay i gotta use integrating factors

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0dy/dt = 5y + Sin(3t)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0by method of undetermined coefficients if possible

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0dy = 5y dt + Sin3t dt 5y dt + Sin3t dt  dy = 0 (5y + Sin3t)dt = dy

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0(5y + Sin3t)dt  dy = 0 (5y  Sin3t)dt + dy = 0 Now let M = (5y  Sin3t) and N = 1

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0My (derivative of M w/h respect to y) is = 5 Nx = 0

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0(My  Nt)/N = (50)/1 = 5 (By the way Nx must be Nt too above)

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0So let's multiply everything in this d.e. by an integrating factor: myu = e^(Integral of 5dx) = e^(5x)

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0(5e^(5x)y  e^(5x)Sin3t)dt + e^(5x)dy = 0

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0Now My = Nt = 5e^(5x)

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0wow sorry about that, i keep confusing t with x, everywhere x means t, now let me just switch to x, cuz i keep getting mixed up... t is same as x, okay?

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0So now Fx ( x ; y ) = M = (5e^(5x)y  e^(5x)Sin3)dx (x is same as t)

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0sorry forgot Sin(3x)

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0F = Integral of M with respect to x.

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0\[F = \int\limits_{}^{}5*e^{5x}y  e^{5x}Sin(3x) dx\]

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0Sorry i'll have to leave now, so just to finish this, integrate that with respect to x to get something like: e^(5x)y .................. +h(y)

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0then you will have: F = e^(5x)y .................. +h(y). Differentiate the expression you get with respect to y to get: Fy = e^(5x)  or plus ............... +h'(y) Set Fy = N and solve for h'(y) then integrate h'(y) to find h(y) and plug that into F(x;y)

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0hey u still here? when is this due... i can email it 2 u 2morrow...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hey sorry, a friend stopped by my room asking for help on a euler's method thing. i have a test over it tomorrow

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0hey ima send u a couple of examples that use the same principle that were solved out by me, sorry im too tired right now

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0okay? gimme ur email...

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0bpw12 gimme an email, i will send u a couple of solved problems that use the same method.. follow them and solve this the same way, sorry too tired now..

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0treeclimberbpw@gmail.com thanks btw.

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0this equation is just like one of those; get it in format Mdx + Ndy = 0

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0and solve like i did...

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0okay lemme just grab a coffee and shove my head into cold water to wake up lol

bahrom7893
 5 years ago
Best ResponseYou've already chosen the best response.0hey emailed you the solution, please click on become a fan if I helped, thanks!
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