(1)原式=(sin10/cos10-√3)*sin80/cos40
=(cos80/sin80-√3)*sin80/cos40
=(cos80-√3sin 80)/cos40
=-2sin(80-30)/cos40
=-2sin50/cos40
=-2cos40/cos40
=-2
(2)原式=(tan60-tan18)/(1+tan60tan18)
=tan(60-18)
=tan42
(1)原式=(sin10/cos10-√3)*sin80/cos40
=(cos80/sin80-√3)*sin80/cos40
=(cos80-√3sin 80)/cos40
=-2sin(80-30)/cos40
=-2sin50/cos40
=-2cos40/cos40
=-2
(2)原式=(tan60-tan18)/(1+tan60tan18)
=tan(60-18)
=tan42