#Degree and Order
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The order of a DE is the order of its highest derivative, while the power of a DE is the highest power of that highest-order derivative (even if derivatives of lower orders have higher powers).
Wait, square? No.
First, let's determine the order. That should be easy.
What will it be?
2?
No.
1
Yes. We have first derivatives, but not second, so order is 1.
As for degree, let's expand the RHS first:
y^(1/2) = y' (x + y'^(1/2))
y^(1/2) = xy' + y'^(3/2)
The order is 1, so look for the highest power of first derivative.
3/2
Nice!
Okay but here comes the problem
Options are 1,3, 3,1, 3,2, 1,2
Order and degree respectively
Which actually
Confuses me
This is not a very good definition I think
or rather in your terms, the power of a first derivative is ill defined
because two differential equations can be the same
in spite of being written differently
e.g. square both sides, or put them both to the power 3
you get the gist
I agree: defining the power of a DE isn't really sensible most of the time. However, that's the definition I've heard of.
The order is the value that's important, anyway.
Oh. Hm... Well, the order is definitely 1.
Yeah, I'm only reacting to this because while I agree with your line of thought, the answer you provided does not match any of the options
So not to criticize you, but just as a gentle reminder that we may be missing some certain criterion
Yeah, that's true.
What criteria could be missing?
I'm currently looking about that
For instance, maybe we need to make sure to write the DE in a certain form?
Perhaps
like, having a power 1 on y
I tried squaring it but it's futile cause the root is left anyway
I would not be all too surprised
And I'm not sure how to compute dy/dx{√(dy/dx)}