别脑补，别相当然

被图片迷惑+1
切忌所有形式的“想当然、脑补”

没有想到利用边长比与角度比的关系

There are a simple reason and misconception as to why people find this question confusing:
--> the 90 degree angle between P and Q seems like it is cut perfectly right down the centre >> to make two 45 degree angles.
--> that's why your brain instinctively thinks the answer is r = sq(3), since the distance seems the same from the left and to the right of the origin!

However, that's the trick to this question and that's why it is CRUCIAL that you train yourself to be highly critical and wary of accepting the simple answer!

Upon closer inspection of the question:

P(-sq(3),1)
Which means the triangle beneath point P has:
height = 1
base = sq(3)
meaning >> radius = 2 (30-60-90 triangle)

PQ不一定垂直于Y轴，P和Q点不是对称的两个点。

还可以，s^2+t^2=4 ,和8=（根3+s )^2+(t-1)^2,求得 s=1，稍麻烦一点

s是横坐标。sin30°=1/2,

这个题求Q点的横坐标，跟P点横坐标互为相反数呀，答案有误。