sin²120°＋cos180°＋tan45°-cos²(-330°)+sin(-210°)数学解答题

sin²120°＋cos180°＋tan45°-cos²(-330°)+sin(-210°)数学解答题
sin²120°＋cos180°＋tan45°-cos²(-330°)+sin(-210°)数学解答题

sin²120°＋cos180°＋tan45°-cos²(-330°)+sin(-210°)数学解答题
sin120°=sin60°=√3/2
cos180° = -1
tan45°=1
cos330° = cos30° = √3/2
sin(-210°) = sin(-360°+150°)=sin150°=sin30°=1/2
原式=3/4 -1 + 1 - 3/4 + 1/2 = 1/2

3/4-1 1-3/4 1/2=1/2