1/sin50-根号3/cos50
=(cos50-根号3sin50)/(sin50cos50)
=2(cos60cos50-sin60sin50)/(sin50cos50)
=4cos110/(2sin50cos50)
=4cos110/sin100
=-4sin20/cos10
=-8sin10
1/sin50-根号3/cos50
=(cos50-根号3sin50)/(sin50cos50)
=2(cos60cos50-sin60sin50)/(sin50cos50)
=4cos110/(2sin50cos50)
=4cos110/sin100
=-4sin20/cos10
=-8sin10