cos(π/3+α)=-3/5,sin(2π/3-β)=5/13,且0
已知cos(π/3+α)=-3/5,sin(2π/3-β)=5/13且0
已知cos(π/3+α)=-3/5,sin(2π/3-β)=5/13,且0
已知α∈(0,π/2),且2sinα-sinαcosα-3cosα=0.求[sin(α+π/4)]/[sin2α+cos
已知cos(α-β/2)=-3/5,sin(α/2-β)=12/13,且α∈(π/2,π),β∈(0,π/2),求cos
已知cos(α-β/2)=-3/5 sin(α/2-β)=12/13 且α∈(π/2,π),β∈(0,π/2),则sin
α属于(0,π/2)且2sin²α-sinαcosα-3cos²α=0求sin(α+π/4)/sin
已知sin(3π/4+α)=5/13 cos(π/4-β)=3/5 ,且0
已知sin(3π-α)=根号2*sin(π-β),根号3*cos(-α)=-根号2*cos(π+β),且α、β∈(0,π
已知sinα+cosα=三分之根号二,sinα-cosα=-4/3,且α∈(-π/2,0),计算(1+sin2α+cos
cos(π/2-α)=根号2cos(3/2π+β),根号3sin(3π/2-α)=-根号2sin(π/2+β)且0
已知α∈(0,π/2),且2sin²α-sinαcosα-3cos²α=0,求[sin(α+π/4)
已知a为第三象限角,且f(a)=sin(5π-a)cos(a+3π/2)cos(π+a)/sin(a-3π/2)cos(