How can I effectively solve two challenging differential equations problems?

In summary, the person is asking for help with two problems from their differential equations assignment. For the first problem, they used reduction of order and got a solution of xe^x. They are wondering if they should use variation of parameters to solve the nonhomogeneous equation and then use it for the general solution. For the second problem, they multiplied by x^p y^q and found the partial derivatives My and Nx. They equated these partial derivatives and got values for p and q, but they were fractions and their final solution was messy. They are asking if this approach is correct.
  • #1
FaradayLaws
8
0

Homework Statement


I have two problems from my differential equations assignment that I'm having difficulty with. I would appreciate some guidance!


Homework Equations



http://img10.imageshack.us/img10/3397/questionsk.th.jpg

The Attempt at a Solution


for no.10 I used reduction of order with the assumption that one solution is y1=e^x
I got y2=xe^x

my question is for this question do I solve the unhomogenous equation by variation of parameters to solve for the particular solution And from there use it for the General Solution ? ( yg= yh+yp.

For no.7
I multiplied by x^p y^q and found the partial derivatives My and Nx.
Inorder for it to be exact, I equated the partial derivatives and found my values for p and q. They came out to being fractions and my final solution is extremely messy with fractions. Is this is correct approach?

Thanks.
 
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  • #2
FaradayLaws said:

Homework Statement


I have two problems from my differential equations assignment that I'm having difficulty with. I would appreciate some guidance!


Homework Equations



http://img10.imageshack.us/img10/3397/questionsk.th.jpg

The Attempt at a Solution


for no.10 I used reduction of order with the assumption that one solution is y1=e^x
I got y2=xe^x

my question is for this question do I solve the unhomogenous equation by variation of parameters to solve for the particular solution And from there use it for the General Solution ? ( yg= yh+yp.
Yes.

for no.7
I multiplied by x^p y^q and found the partial derivatives My and Nx.
Inorder for it to be exact, I equated the partial derivatives and found my values for p and q. They came out to being fractions and my final solution is extremely messy with fractions. Is this is correct approach?
Did you get 3q= 2(p+1) and 20(q-1)= 12(p+ 3)? That's what I got. Yes, those give "messy" fractions.

Thanks.[/QUOTE]
 
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  • #3


I would suggest first reviewing the concepts and techniques for solving differential equations, such as reduction of order and variation of parameters. These are important tools for solving differential equations and understanding the solutions. Additionally, it would be helpful to review the steps for solving exact equations, as mentioned in the Attempt at a Solution for problem no. 7. It is important to carefully check your work and make sure your final solution makes sense mathematically. If you are still having difficulty, it may be helpful to seek assistance from a tutor or your professor. Practice and repetition are key in mastering differential equations, so don't get discouraged and keep working at it. Good luck with your assignment!
 

FAQ: How can I effectively solve two challenging differential equations problems?

What is a differential equation?

A differential equation is a mathematical equation that describes the relationship between a function and its derivatives. It involves a function, its derivatives, and one or more independent variables. It is used to model dynamic systems and is essential in many fields of science and engineering.

What is the difference between an ordinary and partial differential equation?

An ordinary differential equation involves a single independent variable, while a partial differential equation involves multiple independent variables. Ordinary differential equations are used to model one-dimensional systems, while partial differential equations are used to model multi-dimensional systems.

What are the different methods for solving a differential equation?

There are several methods for solving differential equations, including separation of variables, substitution, integrating factors, power series, and numerical methods such as Euler's method and Runge-Kutta methods. The method used depends on the type and complexity of the equation.

How are differential equations used in science?

Differential equations are used in many areas of science, including physics, chemistry, biology, economics, and engineering. They are used to model and understand natural phenomena, predict future behavior of systems, and make scientific predictions and discoveries.

What are the applications of differential equations?

Differential equations have a wide range of applications, such as modeling population growth, predicting weather patterns, designing control systems, analyzing circuits, and understanding chemical reactions. They are also used in fields such as finance, medicine, and ecology.

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