Definition

Examples

• 从圆外一点可以画两条切线。
  Cóng yuán wài yì diǎn kěyǐ huà liǎng tiáo qiē xiàn.
  From a point outside the circle, two tangents can be drawn.
• 切线与半径互相垂直。
  qiē xiàn yǔ bànjìng hùxiāng chuízhí.
  The tangent is perpendicular to the radius.
• 这道题要求求出切线的长度。
  Zhè dào tí yāoqiú qiú chū qiē xiàn de chángdù.
  This problem asks you to find the length of the tangent.