题目如图,ABABAB是⊙O⊙O⊙O的直径,弦CD⊥ABCD⊥ABCD⊥AB于点EEE,点FFF在\overparenBC\overparen{BC}\overparenBC上,AFAFAF与CDCDCD交于点GGG,点HHH在DCDCDC的延长线上,且HG=HFHG=HFHG=HF,延长HFHFHF交ABABAB的延长线于点M.M.M.(1)(1)(1)求证:HFHFHF是⊙O⊙O⊙O的切线;(2)(2)(2)若sinM=45\sin M=\dfrac{4}{5}sinM=54,BM=1BM=1BM=1,求AFAFAF的长.知识点:切线的判定与性质章节:图形的性质 / 圆