Do I need to draw a tangent line of this circle?
我需要画出这个圆的一条切线吗？
On this basis, a practical simple way to construct by the conical curves the common tangent circle is presented.
在此基础上，提出了简便、实用的圆锥曲线公切圆作图法。
Life is a circle, some people walk all his life did not make fate draw a circle, each point on the circle have a tangent to take-off.
人生是个圆，有的人走了一辈子也没有走出命运画出的圆圈，圆上的每一个点都有一条腾飞的切线。
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