解方程:(x+2005)/(x+2004)+(x+2007)/(x+2006)=(x+2008)/(x+2007)+(x+2004)/(x+2003)
问题描述:
解方程:(x+2005)/(x+2004)+(x+2007)/(x+2006)=(x+2008)/(x+2007)+(x+2004)/(x+2003)
答
换元吧,令x+2005=t则t/(t-1)+(t+2)/(t+1)=(t+3)/(t+2)+(t-1)/(t-2)1+1/(t-1)+1-1/(t+1)=1+1/(t+2)+1-1/(t-2)∴ 2/(t²-1)=-4/(t²-4)∴ 4(t²-1)=2(t²-2)∴ 2t²=0∴ t=0即x=-2005经检验,是方...