Current location - Training Enrollment Network - Mathematics courses - Yunnan mathematics middle school entrance examination questions
Yunnan mathematics middle school entrance examination questions
(2) Practical application

As shown in figure (3), make a chord BE⊥CD at point B, connect AE and CD at point P, and connect OB, OE, OA and PB.

∵BE⊥CD,

∴CD bisects BE, that is, point E and point B are symmetrical about CD.

∵AC? It's 60 degrees, point b is the midpoint of AC,

∴∠BOC=30,∠AOC=60,

∴∠EOC=30,

∴∠AOE=60 +30 =90,

∫OA = OE = 1,

∴AE=2OA=√2

The length of AE is the minimum value of BP+AP. ∴BP+AP=√2

(3) Expansion and extension

As shown in Figure (4), that is, point P is the symmetrical point E about straight line AB, point P is the symmetrical point F about straight line BC, and EF is connected to points M and N of AB and BC respectively.

Hope to adopt thank you!