求sin(-1200°）×cos1290°+cos9-1020°)×sin（-1500°）+tan95°
问题描述：
求sin(-1200°）×cos1290°+cos9-1020°)×sin（-1500°）+tan95°
答
sin(-1200°）×cos1290°+cos(-1020°)×sin（-1500°）+tan95°
=sin(-1200°+1080°）×cos(1080°+210°)+cos(-1020°+1080°)×sin（-1500°+1440°）+tan95°
=sin(-120°）×cos(210°)+cos60°×sin（-60°）+tan95°
=-sin120°×cos(180°+30°)-cos60°×sin60°+tan95°
=sin60°cos30°-cos60°×sin60°+tan95°
=√3/2*√3/2-1/2×√3/2+tan95°
=3/4-√3/4+tan95°