Triagles WXY and ZXW are similar, so WX^2 = XY * XZ.

Angle XWY = Tangent angle between the tangent line and YX = Angle XZW

Triagles WXY and ZXW are similar, so WX^2 = XY * XZ.

Hence, XZ = 64/14 and YZ = 14 - (64/14).

 

 

所有跟帖： 

• I think you are right... -borisg- ♂ (0 bytes) () 01/29/2021 postreply 14:51:48

• 赞！俺贴到高中和大学群里看看谁还会做。-：） -有言- ♂ (0 bytes) () 01/29/2021 postreply 14:59:22

• 看不出similar 啊 -眼镜- ♂ (0 bytes) () 01/29/2021 postreply 15:09:29

• 角XWZ=角WYX 因爲角對應圓上的arc是一樣長 -violinpiano- ♂ (0 bytes) () 01/29/2021 postreply 15:26:43

• 是similar.厉害！ -眼镜- ♂ (0 bytes) () 01/29/2021 postreply 15:46:14

• 谢谢，昨天做了半小时，没想到用相似。 -rapidestate- ♂ (0 bytes) () 01/29/2021 postreply 16:37:21