
我这才是巧解:
解:把原方程两边同时加1得:
x²+〔x²+(x+1)²〕/(x+1)²=4.
x²+〔(2x²+2x)+1〕/(x+1)²=4.
x²+〔2x(x+1)+1〕/(x+1)²=4.
x²+2x·1/(x+1)+1/(x+1)²=4
〔x+1/(x+1)〕²=4, x+1/(x+1)=±2.
x²+x+1=±2(x+1),解此一元二次方程得:x=(1±√5)/2.
我这才是巧解:
解:把原方程两边同时加1得:
x²+〔x²+(x+1)²〕/(x+1)²=4.
x²+〔(2x²+2x)+1〕/(x+1)²=4.
x²+〔2x(x+1)+1〕/(x+1)²=4.
x²+2x·1/(x+1)+1/(x+1)²=4
〔x+1/(x+1)〕²=4, x+1/(x+1)=±2.
x²+x+1=±2(x+1),解此一元二次方程得:x=(1±√5)/2.