Eigenvalues โ€‹โ€‹- Help classify the first-order PDE system to be elliptic, hyperbolic, or parabolic

The question I need help with is in the picture.


I have already added the system to the form
Aq_x + Bq_y = C,

A =
begin {bmatrix}
a_1 & 0 \
0 & b_1
end {bmatrix}, quad B =
begin {bmatrix}
0 & a_2 \
b_2 & 0
end {bmatrix}, quad q =
begin {pmatrix}
u \
end {pmatrix}.

But I do not know how to proceed from here to find out the eigenvalues โ€‹โ€‹of the term
C =
begin {pmatrix}
g_1 \

that confuses me.
If $ C $ were $ 0 $Then I know how to proceed, but unfortunately that is not the case.

Any help would be appreciated.

Tagging – What software can use a batch of classified images and automatically learn from them to automatically classify them for more images?

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I want to automatically classify images based on the tags I've assigned to the already classified images.

Most steps (I use Lightroom) are simple:

  • write XMP files
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  • feeds every set of images (one set per day) to software
  • Use the output of the software to write new XMP files
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However, which (artificial intelligence) software can I use for this purpose?

The question is asked here in Photo because I am asking for a finished or almost finished package, not the software / package that is to be used when programming a new AI.

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Limitation of an app, only allowed for specific users who meet the requirements.

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First, the user should be registered on the website.
Second, the user has paid a certain amount for the application.

Is there a way to do this? or any suggestions?

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