求值： 2(sin^6 θ+cos^6 θ)-3(sin^4 θ+cos^4 θ)

求值： 2(sin^6 θ+cos^6 θ)-3(sin^4 θ+cos^4 θ) sin(π+π/6)-cos(π+π/4)cos(-π/2)+1求值 sin^a+cos^(π/6+a)+1/2sin(2a+π/6)求值 求值sin²x+cos²(π/6+x)+1/2sin(2x+π/6) 求值:2sinπ/6+sin3π/2-2cosπ+2sinπ/3 求(6sinα+cosα)/(3sinα-2sinα)的值 tan(α/2)=2求值 求值：(1-sin^6 x-cos^6 x)/(1-sin^4 x-cos^4 x) sin(x+π/6)=1/2,则cos(π/3-x)求值 求值：cos^2α-sin^2α 求值sin^2a+cos^2a(π/6+a)+1/2sin(2a+6/π) 求值sin^2α+cos^2(π/6+α)+1)+1/2sin(2α+π/6) 求值sin²α+cos²α(π/6+α)+1/2sin(2α+π/6） 已知6sin²α+sinαcosα-2cos²α=0,α∈（π/2,π）,求值1).(sinα-3cosα）/（sinα-cosα）；2）.sinαcosα-sin²α;3).sin²α-3cosαsinα-2 cos^6(π/8)-sin^6(π/8)=求值,[cos^2(π/8)-sin^2(π/8)][cos^4(π/8)+sin^4(π/8)+cos^2(π/8)sin^2(π/8)]=cos(π/4)[1-cos^2(π/8)sin^2(π/8)]=cos(π/4)[1-[sin^2(π/4)]/4]==7√2/16 若tanα=√2,求值：(1-sin∧6x-cos∧6x)/(1-sin∧4x-cos∧4x) 求值:2cosπ/2-tanπ/4+3/4tan²π/6-sinπ/6+cos²π/6+sin3π/2 -1/4cosπ 已知tanθ=2,求值sin^2θ+sinθcosθ-2cos^2θ 求值:sin的平方α+cosαcos(π/3+α)-sin的平方(π/6-α)