已知α为第三象限角且f(α)=sin(π-α)cos(2π-α)/cos(π/2+α)
已知α为第三象限角且f(α)=sin(π-α)cos(2π-α)/cos(π/2+α)
已知α是第三象限角,且f(α)=sin(π-α)cos(2π-α)tan(-α+3π/2)/cos(-α -π) (1)
②若cos(已知α是第三象限角f(α)=sin(π-α)cos(2π-α)tan(-α-π)/tan(-α)sin(-π
已知sin(π-α)cos(-α+3π/2)/cos(-π-α),且α为第三象限角1.化简f(α)2.若cos(α+π/
已知α为第三象限角,且f(α)=sin(π-α)cos(2π-α)tan(-α+π)/sin(π+α)tan(2π-α)
已知α是第三象限角,且sin+cosα/sinα-cosα=2
已知α是第三象限的角,且f(α)=sin(π−α)cos(2π−α)tan(3π2−α)cos(−π−α).
已知α为第三象限角,且根号下(1-sinα)/(1+sinα)+1/cosα=2,则(sinα-cosα)/(2cosα
已知α是第三象限角,且f(α)=[sin(π+α)cos(2π-α)tan(-α+3π/2)tan(-α-π)]/sin
若sin(α-β)cosα-cos(α-β)sinα=m,且β为第三象限角,则cosβ的值为( )
已知α是第三象限角,且f(α)=[sin(π-α)cos(2π-α)]/sin(3π-α)
已知tanα=2,且α是第三象限角,求sin(kπ -α)+cos(kπ+α)的值