(cosπ12-sinπ12)(cosπ12+sinπ12)= ___ .
(cosπ12-sinπ12)(cosπ12+sinπ12)= ___ .
已知α=7/12π,那么cosα√(1-sinα)/(1+sinα)+sinα√(1-cosα)/(1-cosα)=
cos*π/12—sin*π/12
计算cosπ/12*sinπ/12
求值:sin(π/12)+cos(π/12)
如果A为△ABC的内角,sin(π+A)=-12,那么cos(π-A)= ___ .
(cosπ/12-sinπ/12)*(COSπ/12+sinπ/12)等于
sinπ/24*cosπ/24*sinπ/12=—— 答案是这么写的:1/2(2sinπ/24*cosπ/24)cosπ
根号3×cosπ/12-sinπ/12=?
cos(π/12)^4+sin(π/12)^4=
4 sinπ/12 cosπ/12=
cos5/12πcosπ/12+cosπ/12sinπ/6=?