y'-ytanx=sin2x
cosxy'-ysinx=2sinxcos^2x
(cosxy)'=2sinxcos^2x
(cosxy)=∫2sinxcos^2xdx=-2∫cos^2xdcosx=-2/3* cos^3x+C
即cosxy=-2/3* cos^3x+C
y'-ytanx=sin2x
cosxy'-ysinx=2sinxcos^2x
(cosxy)'=2sinxcos^2x
(cosxy)=∫2sinxcos^2xdx=-2∫cos^2xdcosx=-2/3* cos^3x+C
即cosxy=-2/3* cos^3x+C