α∈(0,π),且2sin(π/3-α)+sinα=3/2,求α
α属于(0,π/2)且2sin²α-sinαcosα-3cos²α=0求sin(α+π/4)/sin
已知α∈(0,π/2),且2sinα-sinαcosα-3cosα=0.求[sin(α+π/4)]/[sin2α+cos
已知α∈(0,π/2),且2sin²α-sinαcosα-3cos²α=0,求[sin(α+π/4)
已知α∈(0,π|2),2tanα+3sinβ=7,且tanα-6sinβ=1,求sinα的值
已知α∈(0,π/2),且2sin²α-sinαcosα-3cos²α.求sin(α+π/4)/si
已知α,β为锐角,且3sin²α+2sin²β=1,3sin²α-2sin(2β)=0,求
已知tanα=2,sinα+cosα<0,求[sin(2π-α)*sin(π+α)*cos(-π+α)]/[sin(3π
sinα=sqr(2)sinβ,sqr(3)cosα=sqr(2)cosβ,且α,β均为三角形内角,求sinα,sinβ
y=sin(2x+π/3+α)为偶函数且α>0求α最小值
已知α∈﹙0,π/2),且2Sinα-SinαCosα-3Cosα=0.求[Sin(α+π/4)]/(Sin2α+Cos
已知3sinα cosα=0,求 3cosα 5sinα/sinα-cosα与sin²α 2sinα
已知α属于(0,pai/2),且2(sinα)^2-sinαcosα-3(cosα)^2=0,求{[sin(α+pai/