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

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SUMMARY

The discussion focuses on using Abel's Formula to find the Wronskian of two solutions for the differential equation x²y" - x(x+2)y' + (t + 2)y = 0. The correct form for p(x) is identified as p(x) = -(x + 2)/x, which is essential for applying Abel's Formula: W(y1, y2)(x) = ce^(-∫p(x)dx). Participants confirm the integration process, leading to the expression W(y1, y2)(x) = ce(x) + 2ln(x), and clarify that the constant c represents the Wronskian evaluated at an initial value x0.

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  • Understanding of differential equations, specifically second-order linear equations.
  • Familiarity with Abel's Formula for Wronskians.
  • Knowledge of integration techniques, particularly with logarithmic functions.
  • Ability to manipulate algebraic expressions, including proper use of parentheses.
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  • Study the derivation and applications of Abel's Formula in differential equations.
  • Practice solving second-order linear differential equations using various methods.
  • Explore the concept of Wronskians and their significance in determining linear independence of solutions.
  • Review integration techniques, focusing on integrating rational functions and logarithmic expressions.
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Students and educators in mathematics, particularly those studying differential equations, as well as researchers and practitioners seeking to apply Abel's Formula in their work.

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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