Finding Wronskian of Diff. Eq. with Abel's Formula: Help Needed

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Homework Help Overview

The discussion revolves around finding the Wronskian of two solutions to a given differential equation using Abel's Formula. The equation presented is a second-order linear differential equation, and participants are exploring the application of Abel's Formula without solving the equation directly.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the formulation of the differential equation to identify the function p(x) for use in Abel's Formula. There is uncertainty regarding the correct placement of parentheses in the expression for p(x). Questions arise about the integration process and the determination of the constant c in the Wronskian.

Discussion Status

The conversation is ongoing, with participants providing feedback on each other's attempts. Some guidance has been offered regarding the integration and the interpretation of the constant c, but there is no explicit consensus on the final form of the Wronskian or its evaluation.

Contextual Notes

Participants are working under the constraint of not solving the differential equation directly, which influences their approach to finding the Wronskian. There is also a focus on ensuring the correct mathematical notation is used throughout the discussion.

physics=world
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1. Use Abel's Formula to find the Wronskian of two solutions of the given differential equation
without solving the equation.


x2y" - x(x+2)y' + (t + 2)y = 0

2.

Abel's Formula

W(y1, y2)(x) = ce-∫p(x)dx3.

I put it in the form of

y" + p(x)y' + q(x)y = 0

to find my p(x) to use for Abel's formulap(x) = - (x+2 / x)this would give:

W(y1, y2)(x) = ce-∫(-)(x+2 / x)dxI'm not sure if I'm going in the right direction. I need some help.
 
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physics=world said:
1. Use Abel's Formula to find the Wronskian of two solutions of the given differential equation
without solving the equation.


x2y" - x(x+2)y' + (t + 2)y = 0

2.

Abel's Formula

W(y1, y2)(x) = ce-∫p(x)dx





3.

I put it in the form of

y" + p(x)y' + q(x)y = 0

to find my p(x) to use for Abel's formula


p(x) = - (x+2 / x)
Your use of parentheses is commendable, although you have them in the wrong place here and below.
You should have p(x) = -(x + 2)/x

What you wrote is the same as ##-(x + \frac 2 x)##.
physics=world said:
this would give:

W(y1, y2)(x) = ce-∫(-)(x+2 / x)dx


I'm not sure if I'm going in the right direction. I need some help.
This seems OK to me (aside from the parentheses thing). Are you having trouble with the integration?
 
After integrating I get:

ce(x) + 2ln(x)

Is this the answer? What about the value for c?
 
physics=world said:
After integrating I get:

ce(x) + 2ln(x)
You should simplify that.
physics=world said:
Is this the answer? What about the value for c?
I believe that c is W(y1(x), y2(x))(x0). IOW, the Wronskian of the two functions, evaluated at some initial x value.
 

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