#1
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please help me
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$a(x-1)^2+b(x+1)^2+c=x^2$ ¨§ËÒ¤èÒ $x$ áÅÐ $y$ ·Õè·ÓãËéÊÁ¡ÒõèÍ仹Õéà»ç¹¨ÃÔ§ÊÓËÃѺ·Ø¡¤èҢͧ $k$ $x^2+y^2+(k-2)x-2ky-k-4=0$ ¢Íº¤Ø³ÁÒ¡æææææ¤èÐ
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#2
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Hint:
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#3
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$$a(x-1)^2+b(x+1)^2+c=x^2$$
$$a(x^2-2x+1)+b(x^2+2x+1)+c=x^2$$ $$(a+b)x^2+(2b-2a)x+(a+b+c)=x^2$$ à·ÕºʻÊ.¨Ðä´é $$a+b=1$$ $$2b-2a=0$$ $$a+b+c=0$$ ¨Ðä´é $a=b=\frac{1}{2} $,$c=-1$ ªéÍ2¡çÊÒÁÒö·Óä´é㹷ӹͧà´ÕÂǡѹ 18 ÊÔ§ËÒ¤Á 2008 21:50 : ¢éͤÇÒÁ¹Õé¶Ù¡á¡éä¢áÅéÇ 1 ¤ÃÑé§, ¤ÃÑé§ÅèÒÊØ´â´Â¤Ø³ nongtum à˵ؼÅ: double post+á¡é䢢éͤÇÒÁàÅ硹éÍ â»Ã´ãªé»ØèÁá¡éä¢ |
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