<=>x+2(2−x+2)=x3−x−6" role="presentation" style="font-size: 13.696px; display: inline; text-align: center; position: relative;"><=>x+2−−−−√(2−x+2−−−−√)=x3−x−6<=>x+2(2−x+2)=x3−x−6<=>x+2(2−xx+2+2)=(x−2)(x2+2x+3)" role="presentation" style="font-size: 13.696px; display: inline; text-align: center; position: relative;"><=>x+2−−−−√(2−xx+2−−−−√+2)=(x−2)(x2+2x+3)<=>x+2(2−xx+2+2)=(x−2)(x2+2x+3)x=2=>>" role="presentation" style="font-size: 13.696px; display: inline; position: relative;">x=2=>>x=2=>>x#2 thì −x+2x+2+2=x2+2x+3" role="presentation" style="font-size: 13.696px; display: inline; position: relative;">−x+2−−−−√x+2−−−−√+2=x2+2x+3−x+2x+2+2=x2+2x+3VP>0VT<0=> loại.x=2
<=>x+2(2−x+2)=x3−x−6" role="presentation" style="font-size: 13.696px; display: inline; text-align: center; position: relative;"><=>x+2−−−−√(2−x+2−−−−√)=x3−x−6<=>x+2(2−x+2)=x3−x−6<=>x+2(2−xx+2+2)=(x−2)(x2+2x+3)" role="presentation" style="font-size: 13.696px; display: inline; text-align: center; position: relative;"><=>x+2−−−−√(2−xx+2−−−−√+2)=(x−2)(x2+2x+3)<=>x+2(2−xx+2+2)=(x−2)(x2+2x+3)x=2=>>" role="presentation" style="font-size: 13.696px; display: inline; position: relative;">x=2=>>x=2=>>x#2 thì −x+2x+2+2=x2+2x+3" role="presentation" style="font-size: 13.696px; display: inline; position: relative;">−x+2−−−−√x+2−−−−√+2=x2+2x+3−x+2x+2+2=x2+2x+3VP>0VT<0=> loại.=> x=2 là nghiệm duy nhất./
<=>x+2(2−x+2)=x3−x−6" role="presentation" style="font-size: 13.696px; display: inline; text-align: center; position: relative;"><=>x+2−−−−√(2−x+2−−−−√)=x3−x−6<=>x+2(2−x+2)=x3−x−6<=>x+2(2−xx+2+2)=(x−2)(x2+2x+3)" role="presentation" style="font-size: 13.696px; display: inline; text-align: center; position: relative;"><=>x+2−−−−√(2−xx+2−−−−√+2)=(x−2)(x2+2x+3)<=>x+2(2−xx+2+2)=(x−2)(x2+2x+3)x=2=>>" role="presentation" style="font-size: 13.696px; display: inline; position: relative;">x=2=>>x=2=>>x#2 thì −x+2x+2+2=x2+2x+3" role="presentation" style="font-size: 13.696px; display: inline; position: relative;">−x+2−−−−√x+2−−−−√+2=x2+2x+3−x+2x+2+2=x2+2x+3VP>0VT<0=> loại.x=2