cos1110度等于多少
cos1110°的值为( )A.12B.32C.-12D.-3 -
cos1110°=cos(3×360°+30°)cos30°=32,故选:B.
所以cos1110度=√3/2(“√”是根号)
cos1110°=cos(3×360°+30°)cos30°=32,故选:B.
所以cos1110度=√3/2(“√”是根号)
回答:二分之根号三
=sin(-1320°+360°x4)=sin(120°)=√3/2 cos1110° =cos(1110°-360°x3)=cos30° =√3/2 cos(-1020°)=cos(-1020°+360°x3)=cos60° =1/2 sin750° =sin(750°-360°x2)=sin30° =1/2 tan495° =tan(495°-360°)=tan135° =tan(180°-45°)=-tan45° =-1 您还有呢?
问一道数学题 sin(-1320)乘以cos1110+cos(-1020)乘以sin720,最后再加上...
sin(-1320)cos1110+cos(-1020)sin720+tg495=sin(-1320+360x4)cos(1110-360x3)+cos(-1020+360x3)sin(720-360x2)+tg(495-360)=sin120cos30+0+tg135=sin60cos30-1=3/4-1=-1/4
cos(1110°)cos1110°=cos(1080°+30°)cos30°=32.故答案为:32
sin(-1320°)cos1110°的值 -
1
请采纳,
化简:sin780°cos1110°+cos(-660°)sin(-690°)+tan585°cos1440°
sin(2x360+60)cos(3x360+30)+cos(-2x360+60)sin(-2x360+30)+tan(360+225)cos(4x360)=sin60cos30+cos60sin30+tan(180+45)=√3/2 x √3/2+1/2 x 1/2 - √2/2 =1-√2/2
sin-1320*cos1110+cos-1020*sin750+tan(360+135) =sin(-360*4+120)cos(3*360+30)+cos(-360*3+60)*sin(360*2+30)+tan135 =sin120cos30+cos60sin30+tan135 =3/4+1/4-1=0 主要注意这个公式的应用:sin(360*K+a)=sina 其中的K为任意整数,可为正也可为负,所以在求大于360的角度希望你能满意。