sinx×cos2x-sin2x×cosx

来源：学生作业帮编辑：大师作文网作业帮分类：数学作业时间：2024/11/10 18:32:22

sinx×cos2x-sin2x×cosx
=sin(x-2x)
=-sinx

sinx×cos2x-sin2x×cosx 解方程 sin2x/sinx=cos2x/cosx sin3x+cosx-cos3x-sinx/2(sin2x+cos2x) 化简:(sinx+sin2x)/(1+cosx+cos2x) cos2x+cosx=0,则sin2x+sinx 怎么证明cos2x/1-sin2x = cosx+sinx/cosx-sinx sin2x/(1+cos2x)*cosx/(1+cosx)*sinx/(1-cosx) 求证:(1-2sinx×cosx)/cos2x-sin2x=(cos2x-sin2x)/(1+2sinx×cosx) 已知sinx=-1/2cosx,cosx-sinx/cosx+sinx+sin2x+cos2x的值 Cosx+sinx分之1+sin2x+cos2x=2cos 证明 (sinx^2+sin2x)/(cosx^2=cos2x)等于多少 cos2x+cosx=0 求sin2x+sinx的值