sin(-2/3π+kπ)cos(π/6+kπ)tan(π/4+kπ)=sin(-2/3π+kπ)cos(π/6+kπ)tan(π/4)=sin(-2/3π+kπ)cos(π/6+kπ)当k是奇数时,原式=[-sin(-2/3π)][-cos(π/6)]=sin(-2/3π)cos(π/6)=-(根号3/2)*(根号3/2)=-3/4当...