求sin50度(1+根号3倍的tan10度)的值

问题描述:

求sin50度(1+根号3倍的tan10度)的值

=sin50(1+tan60tan10)
=sin50(tan60-tan10)/tan(60-10)
=cos50(tan60-tan10)
=cos50(sin60cos10-sin10cos50)/cos60cos10
=cos50sin50/cos60cos10
=cos10/(2*1/2*cos10)
=cos10/cos10
=1