题目如图,点PPP为⊙O\odot O⊙O外一点,PAPAPA为⊙O\odot O⊙O的切线,AAA为切点,POPOPO交⊙O\odot O⊙O于点BBB,∠P=30∘\angle P=30^{\circ}∠P=30∘,OB=3OB=3OB=3,则线段BPBPBP的长为____.知识点：垂径定理章节：图形的性质 / 圆
如图,点为外一点,为的切线,为切点,交于点,,,则线段的长为____.如图,点为外一点,为的切线,为切点,交于点,,,则线段的长为____.如图,点为外一点,为的切线,为切点,交于点,,,则线段的长为____.