Help Solving ODE: 5x2y2 - 2x3y2 = 1

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In summary, the conversation is about a student struggling with a differential equations problem and seeking help. The problem is to show that 5x2y2 - 2x3y2 = 1 is an implicit solution of the differential equation x(dy/dx) + y = x3y3 on the interval 0 < x < 5/2. The student has attempted to find the derivative dy/dx and solve for y explicitly, but is unsure if their answer is correct. The expert advises using implicit differentiation to solve the problem and provides the correct solution.
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so I'm in my second week of my first differential equations class, and i can't seem to get this problem.

Show that 5x2y2 - 2x3y2 = 1 is an implicit solution of the differential equation x(dy/dx) + y = x3y3 on the interval 0 < x < 5/2

for dy/dx, i got (3xy-5y)/(5x-4x2), I'm pretty sure it's right, but if it's not then it might be why i can't quite get this. i also solved for y explicitly, but then i realized i could just factor it out.

well that's what i did, and all i end up with is just a big polynomial... I'm sure I'm doing it wrong. help please?

edit: alright alright i just saw the sticky... truth be told i just google differential equations forum and signed up real quick to post this, so i was in a hurry. sorry i posted this is the wrong forum :(
 
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b3n5p34km4n said:
so I'm in my second week of my first differential equations class, and i can't seem to get this problem.

Show that 5x2y2 - 2x3y2 = 1 is an implicit solution of the differential equation x(dy/dx) + y = x3y3 on the interval 0 < x < 5/2

for dy/dx, i got (3xy-5y)/(5x-4x2), I'm pretty sure it's right, but if it's not then it might be why i can't quite get this. i also solved for y explicitly, but then i realized i could just factor it out.
No, that derivative is not right. Just use "implicit differentiation" to get [itex]10xy^2dx+ 10x^2ydy- 5x^2y^2dx- 4x^3y dy= 0[/itex]. Rearrange those to [itex](10xy^2- 5x^2y)dx+ (10x^2y- 4x^3y)dy= 0[/itex]. That, now, is the same as [itex]dy/dx= -(10xy^2- 5x^2y)/(10x^2y- 4x^3y)[/itex]. Factor and reduce that.

well that's what i did, and all i end up with is just a big polynomial... I'm sure I'm doing it wrong. help please?

edit: alright alright i just saw the sticky... truth be told i just google differential equations forum and signed up real quick to post this, so i was in a hurry. sorry i posted this is the wrong forum :(
 

1. What is an ODE?

An ODE, or ordinary differential equation, is a type of mathematical equation that involves an unknown function and its derivatives. It is commonly used to model relationships in various scientific fields, such as physics, biology, and engineering.

2. What is the difference between an ODE and a PDE?

An ODE involves only one independent variable, while a PDE (partial differential equation) involves multiple independent variables. Additionally, the derivatives in an ODE are ordinary derivatives, while the derivatives in a PDE are partial derivatives.

3. How do you solve an ODE?

The method for solving an ODE depends on its type and complexity. Some common techniques include separation of variables, integrating factors, and using power series. In some cases, numerical methods may also be used to approximate a solution.

4. What is the solution to 5x2y2 - 2x3y2 = 1?

The solution to this ODE is dependent on the initial conditions or boundary conditions that are given. Without any additional information, it is not possible to determine a unique solution.

5. What are some real-world applications of ODEs?

ODEs are used to model a wide range of phenomena in the natural and physical sciences, such as population growth, chemical reactions, and electrical circuits. They are also used in engineering to model systems such as heat transfer, fluid dynamics, and control systems.

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