求值:2sinπ/6+sin3π/2-2cosπ+2sinπ/3

求值:2sinπ/6+sin3π/2-2cosπ+2sinπ/3 求值:2cosπ/2-tanπ/4+3/4tan²π/6-sinπ/6+cos²π/6+sin3π/2 -1/4cosπ sin3π/2= sinπ/6,sin1,sin3较大小[cos2=sin(π/2-2)] 求值:lg2+log3 27+lg5+3^(1-log3 2)+A(2 3)+sin3π/2 (sinπ/12)-(sin5π/12)+(2sinπ/8)(sin3π/8) sinπ/12-sin5π/12+2sinπ/8sin3π/8 已知sinα+sinβ=根号3(cosβ-cosα),α,β∈(0,π/2),求证：sin3α+sin3β=0 求值sin(60°+α/2)×cos(30°-α/2)× (sin2/α ÷ sin3α/2) 计算sin^2 (π/4)-cos^2 (π/4) * cosπ+3/4π^2 (π/6)+sin3π/2 cosπ/3+tanπ/4+3tan²π/6+sinπ/2+cosπ+sin3π/2等于?. sin3/7π*cos2/5π-cos(-3/7π)*sin(-2/5π) 求值sin^2(α-π/6)+sin^2(α+π/6)-sin^2α sin6分之π+sin3分之π+sin2分之π+sin3分之2π+sin6分之5π+sinπ的值 求证sin3*sin1=sin^2(2)-sin^2(1) 求值:arcsin(sin3π/4)rt 化简 (1)、sin(α+180度)cos(-α)sin(-α-180度) (2)、sin3(-α)cos(2π+α)tan(- n大于等于1,θ不是π的倍数,求证sinθ+sin3θ+...+sin((2n-1)θ)=sin^2(nθ)/sinθ