Solving Inhomogeneous Differential Equations with ODE Particular Solution

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The discussion centers on solving the inhomogeneous differential equation y'' + 2y = 6x + 4. The original poster struggles with finding a solution method beyond inspection. Other participants suggest using the method of undetermined coefficients or finding an annihilator for the right-hand side. Ultimately, the poster realizes that the function 2 + 3x is a suitable particular solution. The conversation highlights the effectiveness of inspection in certain cases while exploring alternative methods for solving differential equations.
sleventh
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Hi all,
I've been staring at this for much to long:

y''+2y=6x+4

what were going over now is homogeneous and inhomogeneous differential equations but i can't seem to think of a method for solving this one other then by inspection. Thank you very much for your help.
 
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In this case, inspection works quite nicely. What's wrong with that?

If you don't like that, you can try the method of undetermined coefficients or try to find an annihilator of the right hand side.
 
i don't like inspection since i haven't found a function that would fit! haha. but thank you, at least i'll stop my wild goose chance for adaptations on integrating factor or separation
 
AH! 2+3x works, silly me.
 
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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