初一下课时导航70页题若(x-1/x)+B=(x+1/x)^2,则B=________(a+b)^2=(a-b)^2+______若(x+y)^2=9,(x-y)^2=5,则xy=_______若x^2+1/x^2=7,则x+1/x=_______

来源:学生作业帮助网 编辑:六六作业网 时间:2024/11/16 11:36:42
初一下课时导航70页题若(x-1/x)+B=(x+1/x)^2,则B=________(a+b)^2=(a-b)^2+______若(x+y)^2=9,(x-y)^2=5,则xy=_______若x^

初一下课时导航70页题若(x-1/x)+B=(x+1/x)^2,则B=________(a+b)^2=(a-b)^2+______若(x+y)^2=9,(x-y)^2=5,则xy=_______若x^2+1/x^2=7,则x+1/x=_______
初一下课时导航70页题
若(x-1/x)+B=(x+1/x)^2,则B=________
(a+b)^2=(a-b)^2+______
若(x+y)^2=9,(x-y)^2=5,则xy=_______
若x^2+1/x^2=7,则x+1/x=_______

初一下课时导航70页题若(x-1/x)+B=(x+1/x)^2,则B=________(a+b)^2=(a-b)^2+______若(x+y)^2=9,(x-y)^2=5,则xy=_______若x^2+1/x^2=7,则x+1/x=_______
B=(x+1/x)^2-(x-1/x)
(a+b)^2=(a-b)^2+4ab
若(x+y)^2=9,(x-y)^2=5,则xy=1
若x^2+1/x^2=7,则x+1/x=±3