Ask your own question, for FREE!
Mathematics 8 Online
OpenStudy (anonymous):

dy/dx=y-2y^2

OpenStudy (anonymous):

and what do you want?

OpenStudy (amistre64):

ode :)

OpenStudy (anonymous):

solution equation, initial condition is (0,100) i only need a hint on finding:\[\int\limits_{}^{}1\div(y-2y ^{2})\] i dont want much more help beyond that

OpenStudy (anonymous):

I'm not so into the integrals, sorry.

OpenStudy (amistre64):

y' = y -2y^2 it looks like youd just reintegrate each term seperately

OpenStudy (anonymous):

that was the starting equation, i then wrote it as dy/dx and then dy/y-2y^2=dx

OpenStudy (anonymous):

i cant figure out how to take the integral of 1/(y-2yy)

OpenStudy (amistre64):

helps if I keep track of the problem I spose :)

OpenStudy (amistre64):

wiat, which equation you wanting to suit up?

OpenStudy (anonymous):

I think you should use partial fractions

OpenStudy (anonymous):

oh, ok y'=y-2y^2 dy/dx=y-2y^2 dy=(y-2y^2)dx dy/(y-2y^2)=dx integrate both

OpenStudy (anonymous):

ahhh partial fractions!!! that should do it! thanks!!

OpenStudy (anonymous):

aww yeah

OpenStudy (anonymous):

that gives me an imaginary constant of integration -.-

OpenStudy (anonymous):

lol, did the integral work out though? I didn't really read the problem

OpenStudy (amistre64):

would y=e^x ??

OpenStudy (amistre64):

and by that I mean: y = e^x + e^2x +C ?? just wondering

OpenStudy (amistre64):

e^x - e^x^2....

OpenStudy (anonymous):

hold on, ill upload a picture in a sec

OpenStudy (anonymous):

can you just injtegrate the original equation (y'=y-2y^2) to (f(y)+c=1/2 y^2 - 2/3 y^3)

OpenStudy (anonymous):

?

OpenStudy (anonymous):

I don't see why not, and then use you initial condition for c.

OpenStudy (anonymous):

uilfha thats pathetic, why bother doing the whole dy/dx sub when i could do that ><

OpenStudy (anonymous):

And then I guess solve 0=1/2(100)^2-2/3(100)^3+c for c?

OpenStudy (anonymous):

thats like -661,666.66...

OpenStudy (anonymous):

lol, that whats confusing me. But that seems to be what they mean by the initial condition (0,100) , and thats how you would do it if you wanted the equation for x(y)

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!