AP Test Practice | DE Homework: Sketch Slope Field

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Homework Statement



Consider the differential equation \frac{dy}{dx} = 2x - y

On the axes provided, sketch a slope field for the given differential equation at the twelve points indicated, and sketch the solution curve that passes through the point (0, 1).

Homework Equations



\frac{du}{dx} = u where u = 2x - y

The Attempt at a Solution



\frac{dy}{dx} = 2x - y

\frac{du}{dx} = u where u = 2x - y

u' = 2 - \frac{dy}{dx}Then what do I do? I have no clue where to go from here.
Is this a homogeneous differential equation?

I know what to do in regards to the rest of the problem, I just don't know how to separate so I can integrate. Do I use the substitution method or integrating factors?
 
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du/dx isn't equal to u. dy/dx=u. What is du/dx? Try to write the differential equation completely in terms of u instead of y. Then separate it.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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