How do I integrate dy/dt=ay-b in differential equations?

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The discussion centers on solving the differential equation dy/dt = ay - b. The correct approach involves factoring out 'a' to rewrite the equation as dy/dt = a(y - b/a). The user correctly identifies the need to integrate both sides, leading to the solution ln |y - (b/a)| = at + c. The confusion arises from the integration process, where the user mistakenly derives ln(ay - b) instead of the correct form.

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agent_509
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I am just getting started on learning differential equations, and I'm stuck on this one:

dy/dt=ay-b​

the book tells me to factor out the a, and then divide

dy/dt=a(y-b/a)

(dy/dt)/(y-b/a)=a​

This is where I get stuck, it completely skips over what to do next and just says to integrate both sides, and you come up with this

ln | y – (b/a) | = at + c
I multiplied both sides by dt to get

[1/(y-b/a)]dy=a dt​

but I don't see how integrating both sides gets the above equation, I instead get

ln(ay-b)=at+c​


what am I doing wrong?
 
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