document.write( "Question 964357: sopve the differential equation : \r
\n" ); document.write( "\n" ); document.write( "(x^2-y^2)*dy=2xy*dx\r
\n" ); document.write( "\n" ); document.write( "1. dy*6x+dy(-y^2)=2x^2yd
\n" ); document.write( "2. 6dyx-dy^3-2x^2yd=0
\n" ); document.write( "3. d(6yx-y^3-2x^2y)=0
\n" ); document.write( "4. d=0
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Algebra.Com's Answer #641533 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
\"%28x%5E2-y%5E2%29dy=2xydx+\" is an example of an Euler-homogeneous DE of degree 2.\r
\n" ); document.write( "\n" ); document.write( "This can be solved by the substitution x = vy.
\n" ); document.write( "==> dx = vdy + ydv.\r
\n" ); document.write( "\n" ); document.write( "==> \"%28x%5E2-y%5E2%29dy=2xydx+\" <==> \"%28v%5E2y%5E2-y%5E2%29dy=2%28vy%29y%28vdy%2Bydv%29+\"\r
\n" ); document.write( "\n" ); document.write( "==> \"%28v%5E2+-+1%29dy+=+2v%5E2dy%2B2vydv\"\r
\n" ); document.write( "\n" ); document.write( "<==> \"-2vydv+=+%281%2Bv%5E2%29dy\"\r
\n" ); document.write( "\n" ); document.write( "<==> \"%28%282v%29%2F%281%2Bv%5E2%29%29dv+=+-dy%2Fy\"\r
\n" ); document.write( "\n" ); document.write( "==> \"ln%281%2Bv%5E2%29+=+-lny+%2B+lnC\"
\n" ); document.write( "==> \"ln%28y%281%2Bv%5E2%29%29+=+lnC\"
\n" ); document.write( "==> \"y%281%2Bv%5E2%29+=+C\"
\n" ); document.write( "==> \"y%281%2Bx%5E2%2Fy%5E2%29+=+C\"
\n" ); document.write( "==> \"y%2Bx%5E2%2Fy+=+C\"
\n" ); document.write( "==> \"x%5E2+%2B+y%5E2+=+Cy\", the general solution to the original DE.\r
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