显然可以,因为cos是偶函数.
cos(-23π/5) 一下子就可以看出等于 cos23π/5
0
0
4个回答
-
00
更多回答
相关问题
-
为什么sin(23π/5) = sin(3π/5) ,cos(17π/4) = cos(π/4)?00
-
tan(13π/3)+sin(-5π/2)+cos(-23π/6)00
-
判断下列三角函数符号sin(-17/5派),cos(-23/4π),cos940°,cos-59/17π00
-
计算 ①tan600°-cos960°-sin(-300°)② tan(-5π/6)+cos(-23π/4)+sin-100
-
cosπ/5·cos2π/5等于多少?00
-
tan675°+1/tan765°-sin(-5π/2)+1/cos(-23π/6)00
-
cosπ5cos2π5的值等于( )00
-
可以这样做吗 cos(a-π)=-5/13 cos(-π+a)=-5/13 -cos(π-a)=-5/13 cos(π-00
-
求值sin7π/3cos(-23π/6)+tan(-11π/4)cos13π/300
-
cosπ/5*cos2π/5 =(2sinπ/5*cosπ/5*cos2π/5)/(2sinπ/5) =(sin2π/500