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

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To find the Wronskian of two solutions of the differential equation x²y" - x(x+2)y' + (t + 2)y = 0 using Abel's Formula, the equation must be rewritten in standard form to identify p(x). The correct form for p(x) is - (x + 2)/x, which leads to the expression W(y1, y2)(x) = ce^(-∫(x + 2)/x dx). After integrating, the result simplifies to ce(x) + 2ln(x), with c representing the Wronskian evaluated at an initial value x0. The discussion emphasizes the importance of proper notation and integration in applying Abel's Formula correctly.
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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.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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