钟表上8点到9点之间,时针和分针在什么时刻重合,又在什么时刻成15°角!

(8*5)/(1-5/60)
=40/(1-1/12)
=40/(11/12)
=40*(12/11)
=480/11
=43又(7/11)分
钟表上8点到9点之间,时针和分针在8点43又(7/11)分时重合.
(8*5-15*(60/360))/(1-5/60)
=(40-15/6)/(1-1/12)
=(40-2.5)/(11/12)
=37.5/(11/12)
=37.5*(12/11)
=450/11
=40又(10/11)分
(8*5+15*(60/360))/(1-5/60)
=(40+15/6)/(1-1/12)
=(40+2.5)/(11/12)
=42.5/(11/12)
=42.5*(12/11)
=510/11
=46又(4/11)分
钟表上8点到9点之间,时针和分针在8点40又(10/11)分和8点46又(4/11)分时成15°角.