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如图,直线$AB:y=\frac{{\sqrt{3}}}{3}x+b$,其中$B\left(-1,0\right)$,点$A$横坐标为$4$,点$C\left(3,0\right)$,直线$FG$垂直平分线段$BC$.

如图,直线$AB:y=\frac{{\sqrt{3}}}{3}x+b$,其中$B\left(-1,0\right)$,点$A$横坐标为$4$,点$C\left(3,0\right)$,直线$FG$垂直平分线段$BC$.

的有关信息介绍如下:

如图,直线$AB:y=\frac{{\sqrt{3}}}{3}x+b$,其中$B\left(-1,0\right)$,点$A$横坐标为$4$,点$C\left(3,0\right)$,直线$FG$垂直平分线段$BC$.

$(1)$把点$B\left(-1,0\right)$代入直线$AB:y=\frac{{\sqrt{3}}}{3}x+b$中,得$\frac{{\sqrt{3}}}{3}\times \left(-1\right)+b=0$,$\therefore b=\frac{{\sqrt{3}}}{3}$,$\therefore AB$的函数关系式:$y=\frac{{\sqrt{3}}}{3}x+\frac{{\sqrt{3}}}{3}$,当$x=4$时$y=\frac{5}{3}\sqrt{3}$,$\therefore $点$A$的坐标为$(4$,$\frac{5}{3}\sqrt{3})$,设$AC$的函数关系式为:$y=mx+n$,把$A(4$,$\frac{5}{3}\sqrt{3})$,$C\left(3,0\right)$两点坐标代入,得$\left\{\begin{array}{l}{4k+b=\frac{5}{3}\sqrt{3}}\\{3k+b=0}\end{array}\right.$,$\therefore k=\frac{5}{3}\sqrt{3}$,$b=5\sqrt{3}$,$\therefore $直线$AC$的函数表达式为:$y=\frac{5}{3}\sqrt{3}x-5\sqrt{3}$;$(2)$过点$A$作$AF\bot x$轴于点$F$,由点$A(4$,$\frac{5}{3}\sqrt{3})$,$B\left(-1,0\right)$得,$\tan \angle ABF=\frac{AF}{BF}=\frac{\frac{5}{3}\sqrt{3}}{5}=\frac{\sqrt{3}}{3}$,$\therefore \angle ABF=30^{\circ}$,由翻折得$\angle C'BC=60^{\circ}$,$BC=BC'=4$,在$Rt\triangle BGC'$中,$BG=2$,$GC'=2\sqrt{3}$,$\therefore $点$C'$的坐标为$(1$,$2\sqrt{3})$,在$Rt\triangle BDG$中,$\angle DBG=30^{\circ}$,$\therefore DG=\frac{BG}{\sqrt{3}}=\frac{2}{\sqrt{3}}=\frac{2}{3}\sqrt{3}$,$\therefore $点$D$坐标为$(1$,$\frac{2}{3}\sqrt{3})$;$(3)\because $直线$FG$垂直平分线段$BC$,在$FG$上取(2)中的$C'$,$\therefore BC=BC'$,$QB=QC$,由(2)知$\angle CBC'=60^{\circ}$,$\angle CBD=\angle C'BD$,$\therefore \triangle BCC'$是等边三角形,$AB$垂直平分$CC'$,①点$P$在$x$轴上方,如图$2$,$\because \triangle BCC'$和$\triangle PQC$都是等边三角形,$\therefore CC'=CB$,$CP=CQ$,$\angle PCQ=\angle BCC'=60^{\circ}$,$\therefore \angle PCC'=\angle QCB$,$\therefore \triangle PCC'$≌$\triangle QCB\left(SAS\right)$,$\therefore PC'=QB$,$\because QB=QC$,$CP=CQ$,$\therefore PC=PC'$,$\because BC=BC'$,$\therefore PB$垂直平分$CC'$,$\therefore $点$P$与点$A$重合,$\therefore PA$的函数关系式就是$AB$的函数关系式:$y=\frac{{\sqrt{3}}}{3}x+\frac{{\sqrt{3}}}{3}$;②点$P$在$x$轴下方,如图$3$,$\because \triangle BCC'$和$\triangle PQC$都是等边三角形,$\therefore CC'=CB$,$CP=CQ$,$\angle PCQ=\angle BCC'=60^{\circ}$,$\therefore \angle PCCB\angle QCBC'$,$\therefore \triangle PCB$≌$\triangle QCC'\left(SAS\right)$,$\therefore \angle CBP=\angle CC'Q=30^{\circ}$,在$Rt\triangle BHO$中,$BO=1$,$\therefore HO=\tan \angle OBH\cdot BO=\frac{\sqrt{3}}{3}$,$\therefore $点$H$的坐标为$(0$,$-\frac{\sqrt{3}}{3})$,设$BP$的函数关系式为$y=mx+n$,把点$B\left(-1,0\right)$,$H(0$,$-\frac{\sqrt{3}}{3})$代入得,$\left\{\begin{array}{l}{-k+b=0}\\{b=-\frac{\sqrt{3}}{3}}\end{array}\right.$,解得$k=-\frac{\sqrt{3}}{3}$,$b=-\frac{\sqrt{3}}{3}$,$\therefore PA$的函数关系式$y=-\frac{\sqrt{3}}{3}x-\frac{\sqrt{3}}{3}$,综上所述$PA$的函数关系式$y=\frac{\sqrt{3}}{3}x+\frac{\sqrt{3}}{3}$或$y=-\frac{\sqrt{3}}{3}x-\frac{\sqrt{3}}{3}$.

如图,直线$AB:y=\frac{{\sqrt{3}}}{3}x+b$,其中$B\left(-1,0\right)$,点$A$横坐标为$4$,点$C\left(3,0\right)$,直线$FG$垂直平分线段$BC$.

$(1)$把点$B\left(-1,0\right)$代入直线$AB:y=\frac{{\sqrt{3}}}{3}x+b$中,得$\frac{{\sqrt{3}}}{3}\times \left(-1\right)+b=0$,$\therefore b=\frac{{\sqrt{3}}}{3}$,$\therefore AB$的函数关系式:$y=\frac{{\sqrt{3}}}{3}x+\frac{{\sqrt{3}}}{3}$,当$x=4$时$y=\frac{5}{3}\sqrt{3}$,$\therefore $点$A$的坐标为$(4$,$\frac{5}{3}\sqrt{3})$,设$AC$的函数关系式为:$y=mx+n$,把$A(4$,$\frac{5}{3}\sqrt{3})$,$C\left(3,0\right)$两点坐标代入,得$\left\{\begin{array}{l}{4k+b=\frac{5}{3}\sqrt{3}}\\{3k+b=0}\end{array}\right.$,$\therefore k=\frac{5}{3}\sqrt{3}$,$b=5\sqrt{3}$,$\therefore $直线$AC$的函数表达式为:$y=\frac{5}{3}\sqrt{3}x-5\sqrt{3}$;$(2)$过点$A$作$AF\bot x$轴于点$F$,由点$A(4$,$\frac{5}{3}\sqrt{3})$,$B\left(-1,0\right)$得,$\tan \angle ABF=\frac{AF}{BF}=\frac{\frac{5}{3}\sqrt{3}}{5}=\frac{\sqrt{3}}{3}$,$\therefore \angle ABF=30^{\circ}$,由翻折得$\angle C'BC=60^{\circ}$,$BC=BC'=4$,在$Rt\triangle BGC'$中,$BG=2$,$GC'=2\sqrt{3}$,$\therefore $点$C'$的坐标为$(1$,$2\sqrt{3})$,在$Rt\triangle BDG$中,$\angle DBG=30^{\circ}$,$\therefore DG=\frac{BG}{\sqrt{3}}=\frac{2}{\sqrt{3}}=\frac{2}{3}\sqrt{3}$,$\therefore $点$D$坐标为$(1$,$\frac{2}{3}\sqrt{3})$;$(3)\because $直线$FG$垂直平分线段$BC$,在$FG$上取(2)中的$C'$,$\therefore BC=BC'$,$QB=QC$,由(2)知$\angle CBC'=60^{\circ}$,$\angle CBD=\angle C'BD$,$\therefore \triangle BCC'$是等边三角形,$AB$垂直平分$CC'$,①点$P$在$x$轴上方,如图$2$,$\because \triangle BCC'$和$\triangle PQC$都是等边三角形,$\therefore CC'=CB$,$CP=CQ$,$\angle PCQ=\angle BCC'=60^{\circ}$,$\therefore \angle PCC'=\angle QCB$,$\therefore \triangle PCC'$≌$\triangle QCB\left(SAS\right)$,$\therefore PC'=QB$,$\because QB=QC$,$CP=CQ$,$\therefore PC=PC'$,$\because BC=BC'$,$\therefore PB$垂直平分$CC'$,$\therefore $点$P$与点$A$重合,$\therefore PA$的函数关系式就是$AB$的函数关系式:$y=\frac{{\sqrt{3}}}{3}x+\frac{{\sqrt{3}}}{3}$;②点$P$在$x$轴下方,如图$3$,$\because \triangle BCC'$和$\triangle PQC$都是等边三角形,$\therefore CC'=CB$,$CP=CQ$,$\angle PCQ=\angle BCC'=60^{\circ}$,$\therefore \angle PCCB\angle QCBC'$,$\therefore \triangle PCB$≌$\triangle QCC'\left(SAS\right)$,$\therefore \angle CBP=\angle CC'Q=30^{\circ}$,在$Rt\triangle BHO$中,$BO=1$,$\therefore HO=\tan \angle OBH\cdot BO=\frac{\sqrt{3}}{3}$,$\therefore $点$H$的坐标为$(0$,$-\frac{\sqrt{3}}{3})$,设$BP$的函数关系式为$y=mx+n$,把点$B\left(-1,0\right)$,$H(0$,$-\frac{\sqrt{3}}{3})$代入得,$\left\{\begin{array}{l}{-k+b=0}\\{b=-\frac{\sqrt{3}}{3}}\end{array}\right.$,解得$k=-\frac{\sqrt{3}}{3}$,$b=-\frac{\sqrt{3}}{3}$,$\therefore PA$的函数关系式$y=-\frac{\sqrt{3}}{3}x-\frac{\sqrt{3}}{3}$,综上所述$PA$的函数关系式$y=\frac{\sqrt{3}}{3}x+\frac{\sqrt{3}}{3}$或$y=-\frac{\sqrt{3}}{3}x-\frac{\sqrt{3}}{3}$.

如图,直线$AB:y=\frac{{\sqrt{3}}}{3}x+b$,其中$B\left(-1,0\right)$,点$A$横坐标为$4$,点$C\left(3,0\right)$,直线$FG$垂直平分线段$BC$.

$(1)$把点$B\left(-1,0\right)$代入直线$AB:y=\frac{{\sqrt{3}}}{3}x+b$中,得$\frac{{\sqrt{3}}}{3}\times \left(-1\right)+b=0$,$\therefore b=\frac{{\sqrt{3}}}{3}$,$\therefore AB$的函数关系式:$y=\frac{{\sqrt{3}}}{3}x+\frac{{\sqrt{3}}}{3}$,当$x=4$时$y=\frac{5}{3}\sqrt{3}$,$\therefore $点$A$的坐标为$(4$,$\frac{5}{3}\sqrt{3})$,设$AC$的函数关系式为:$y=mx+n$,把$A(4$,$\frac{5}{3}\sqrt{3})$,$C\left(3,0\right)$两点坐标代入,得$\left\{\begin{array}{l}{4k+b=\frac{5}{3}\sqrt{3}}\\{3k+b=0}\end{array}\right.$,$\therefore k=\frac{5}{3}\sqrt{3}$,$b=5\sqrt{3}$,$\therefore $直线$AC$的函数表达式为:$y=\frac{5}{3}\sqrt{3}x-5\sqrt{3}$;$(2)$过点$A$作$AF\bot x$轴于点$F$,由点$A(4$,$\frac{5}{3}\sqrt{3})$,$B\left(-1,0\right)$得,$\tan \angle ABF=\frac{AF}{BF}=\frac{\frac{5}{3}\sqrt{3}}{5}=\frac{\sqrt{3}}{3}$,$\therefore \angle ABF=30^{\circ}$,由翻折得$\angle C'BC=60^{\circ}$,$BC=BC'=4$,在$Rt\triangle BGC'$中,$BG=2$,$GC'=2\sqrt{3}$,$\therefore $点$C'$的坐标为$(1$,$2\sqrt{3})$,在$Rt\triangle BDG$中,$\angle DBG=30^{\circ}$,$\therefore DG=\frac{BG}{\sqrt{3}}=\frac{2}{\sqrt{3}}=\frac{2}{3}\sqrt{3}$,$\therefore $点$D$坐标为$(1$,$\frac{2}{3}\sqrt{3})$;$(3)\because $直线$FG$垂直平分线段$BC$,在$FG$上取(2)中的$C'$,$\therefore BC=BC'$,$QB=QC$,由(2)知$\angle CBC'=60^{\circ}$,$\angle CBD=\angle C'BD$,$\therefore \triangle BCC'$是等边三角形,$AB$垂直平分$CC'$,①点$P$在$x$轴上方,如图$2$,$\because \triangle BCC'$和$\triangle PQC$都是等边三角形,$\therefore CC'=CB$,$CP=CQ$,$\angle PCQ=\angle BCC'=60^{\circ}$,$\therefore \angle PCC'=\angle QCB$,$\therefore \triangle PCC'$≌$\triangle QCB\left(SAS\right)$,$\therefore PC'=QB$,$\because QB=QC$,$CP=CQ$,$\therefore PC=PC'$,$\because BC=BC'$,$\therefore PB$垂直平分$CC'$,$\therefore $点$P$与点$A$重合,$\therefore PA$的函数关系式就是$AB$的函数关系式:$y=\frac{{\sqrt{3}}}{3}x+\frac{{\sqrt{3}}}{3}$;②点$P$在$x$轴下方,如图$3$,$\because \triangle BCC'$和$\triangle PQC$都是等边三角形,$\therefore CC'=CB$,$CP=CQ$,$\angle PCQ=\angle BCC'=60^{\circ}$,$\therefore \angle PCCB\angle QCBC'$,$\therefore \triangle PCB$≌$\triangle QCC'\left(SAS\right)$,$\therefore \angle CBP=\angle CC'Q=30^{\circ}$,在$Rt\triangle BHO$中,$BO=1$,$\therefore HO=\tan \angle OBH\cdot BO=\frac{\sqrt{3}}{3}$,$\therefore $点$H$的坐标为$(0$,$-\frac{\sqrt{3}}{3})$,设$BP$的函数关系式为$y=mx+n$,把点$B\left(-1,0\right)$,$H(0$,$-\frac{\sqrt{3}}{3})$代入得,$\left\{\begin{array}{l}{-k+b=0}\\{b=-\frac{\sqrt{3}}{3}}\end{array}\right.$,解得$k=-\frac{\sqrt{3}}{3}$,$b=-\frac{\sqrt{3}}{3}$,$\therefore PA$的函数关系式$y=-\frac{\sqrt{3}}{3}x-\frac{\sqrt{3}}{3}$,综上所述$PA$的函数关系式$y=\frac{\sqrt{3}}{3}x+\frac{\sqrt{3}}{3}$或$y=-\frac{\sqrt{3}}{3}x-\frac{\sqrt{3}}{3}$.