求方程的整数解:2x^2+5xy+2y^2=2007(要过程)

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求方程的整数解:2x^2+5xy+2y^2=2007(要过程)
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求方程的整数解:2x^2+5xy+2y^2=2007(要过程)
求方程的整数解:2x^2+5xy+2y^2=2007(要过程)

求方程的整数解:2x^2+5xy+2y^2=2007(要过程)
提示:原式=(2x+y)*(x+2y)=2007=1*2007=3*669=3*3*223

2X^2+5XY+2Y^2=2007 (2x+y)(x+2y)=2007 2007=1*3*3*223 (1)(2x+y)(x+2y)=1*2007 2x+y=1 x+2y=2007 解得:x=-2005/3(不符题意,舍) (2)(2x+y)(x+2y)=3*669 2x+y=3 x+2y=669 解得:x=-221;y=445 或者: 2x+y=669 x+2y=3 解得:x=445,y=-2...

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2X^2+5XY+2Y^2=2007 (2x+y)(x+2y)=2007 2007=1*3*3*223 (1)(2x+y)(x+2y)=1*2007 2x+y=1 x+2y=2007 解得:x=-2005/3(不符题意,舍) (2)(2x+y)(x+2y)=3*669 2x+y=3 x+2y=669 解得:x=-221;y=445 或者: 2x+y=669 x+2y=3 解得:x=445,y=-221 (3)(2x+y)(x+2y)=9*223 2x+y=9 x+2y=223 解得:x=-205/3(舍) 即一共有二组,一组是X=-221,Y=445,另一组是X=445;Y=-221

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