How Can We Solve the Differential Equation dy/dx = 35/(y^(1/8) + 25x^2)?

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Homework Statement


The differential equation dy/dx= 35/(y1/8+25x2y1/8 has an implicit general solution of the form F(x,y)=K. In fact, because the differential equation is separable, we can define the solution curve implicitly by the form F(x)=G(x)+H(y)=K.
Find such solution and then give the related functions requested.


Homework Equations





The Attempt at a Solution


dy/dx=35/(y1/8(1+25x2)
1+25x2/35 dx=y1/8dy
1/35[tex]\int1+25x^2 dx[/tex]=[tex]\int y^(1/8) dy[/tex]
x+25x3/105=8/9y9/8
105(8/9y9/8)-x-253=K
so G(x)=x+25x3 and H(y)=8/9y9/8
 
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The problem is that this is incorrect and I don't know what I did wrong. Can someone see my mistake. Thank You in advance
 
dy/dx=35/(y1/8(1+25x2)
1+25x2/35 dx=y1/8dy
The bolded line is where you went wrong. Look carefully at what you did. It may be easier to see if you wrote it out "properly:"

[tex]\frac{dy}{dx} = \frac{35}{y^{1/8} + y^{1/8}25x^2}[/tex]

[tex]\frac{dy}{dx} = \frac{35}{y^{1/8}(1 + 25x^2)}[/tex]

Edit: I'm assuming the bolded line really reads ((1+25x2)/35)dx=y1/8dy
 
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So when I separate the variables it should be
y1/8dy=[tex]35/1+25x^2 dx[/tex]
 
Assuming you mean y1/8dy=(35/(1+25x2))dx, then yes, that is correct. It is more easily read as (35dx)/(1+25x2) or 35dx/(1+25x2) though, imo.