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3 votes
Subject differential equation
Day. Month.
Year. ..
(y-secx
) dx + tanxdy...o​

User Nya
by
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1 Answer

2 votes


(y-\sec x)\,\mathrm dx+\tan x\,\mathrm dy=0

Divide both side by
\mathrm dx and rearrange terms to get a linear ODE;


\tan x(\mathrm dy)/(\mathrm dx)+y=\sec x

Multiply both sides by
\cos x:


\sin x(\mathrm dy)/(\mathrm dx)+\cos x\,y=1

The left side can be condensed as the derivative of a product:


(\mathrm d)/(\mathrm dx)(\sin x\,y)=1

Integrate both sides, then solve for
y:


\sin x\,y=x+C\implies\boxed{y(x)=x\csc x+C\csc x}

User Curtis Crewe
by
5.3k points