1、化简[sin(360°+α) ×cos(α+180°)]/[sin(-180°-α) ×cos(-α-180°)]
2、已知sin(α-3π)=2cos(α-4π),求[sin(π-α)+5cos(2π-α)]/[2cos(π+α) -sin(-α)]的值
3、记f(x)= a sin(π?x+α)+b cos(π?x+β)+4(a,b, α, β)均为非零实数,若f(2007)=5,求f(2008)的值
4、已知cos((π/6) -α)= 三分之根号三, 求cos((5π/6)+α)-sin^2(α-(π/6))的值
5、设f(θ)=[2cos^3θ+sin^2(2π-θ)+cos(2π-θ)-3]/[2+2cos^2(π+θ)+cos(-θ)],求f(π/3)的值
6、已知π/6<α<2π/3, cos(α+(π/3))=m(m≠0),求tan((2π/3) -α)的值
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