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æ¹æ³äºï¼5sinx+cosy=sinxcosy
两边对xæ±å¯¼å¾ï¼5cosx-(siny)y'=cosxcosy-(sinxsiny)y'
(-siny+sinxsiny)y'=cosxcosy-5cosx
â´y'=dy/dx=(cosxcosy-5cosx)/(-siny+sinxsiny)=(5cosx-cosxcosy)/(siny-sinxsiny)
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