#Degree and Order

52 messages · Page 1 of 1 (latest)

subtle girder
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√y= dy/dx(x+(√dy/dx))
Degree and order?

novel urchinBOT
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haughty bloom
subtle girder
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Ah

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So I'm supposed to square them

haughty bloom
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Wait, square? No.

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First, let's determine the order. That should be easy.

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What will it be?

subtle girder
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2?

haughty bloom
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No.

subtle girder
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1

haughty bloom
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Yes. We have first derivatives, but not second, so order is 1.

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As for degree, let's expand the RHS first:
y^(1/2) = y' (x + y'^(1/2))
y^(1/2) = xy' + y'^(3/2)

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The order is 1, so look for the highest power of first derivative.

subtle girder
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3/2

haughty bloom
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Nice!

subtle girder
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Okay but here comes the problem

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Options are 1,3, 3,1, 3,2, 1,2

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Order and degree respectively

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Which actually

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Confuses me

gritty sandal
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or rather in your terms, the power of a first derivative is ill defined

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because two differential equations can be the same

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in spite of being written differently

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e.g. square both sides, or put them both to the power 3

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you get the gist

haughty bloom
haughty bloom
gritty sandal
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So not to criticize you, but just as a gentle reminder that we may be missing some certain criterion

haughty bloom
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Yeah, that's true.

subtle girder
gritty sandal
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For instance, maybe we need to make sure to write the DE in a certain form?

subtle girder
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Perhaps

gritty sandal
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like, having a power 1 on y

subtle girder
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I tried squaring it but it's futile cause the root is left anyway

gritty sandal
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I would not be all too surprised

subtle girder
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And I'm not sure how to compute dy/dx{√(dy/dx)}

gritty sandal
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Hmm

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Do you have lecture notes about that?

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Maybe your lecturer has different conventions

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everything I see on the internet uses integer powers

subtle girder
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kek

gritty sandal
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Then I am sorry but I cannot provide much help either

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Sorry man

subtle girder
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Oofsies

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It's ait

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I'll just then bet and like