求值cos5π/8*cosπ8
求值cos5π/8*cosπ8
不查表求值:cos5π/12·sinπ/12=
计算cos5∏/8 * cos∏/8 的值
8sin(π/32)cos(π/32)cos(π/16)cos(π/8),求值
计算cos5分之π+cos5分之2π+cos5分之3π+cos5分之4π
cos5/12πcosπ/12+cosπ/12sinπ/6=?
反三角函数求值arccos(cos5π/4)=?arctan(tan4π/3)=?arcsin(sin6)=?
(sin5π/12+cos5π/12)(sinπ/12-cosπ/12)
(sin5π/12-sinπ/12)(cos5π/12+cosπ/12)=?
帮我解,证明恒等式(cos平方5π/12)+(cos平方π/12)+(cos5π/12)(cosπ/12)=5/4
cos方5π/12+cos方π/12+cosπ/12*cos5π/12 最后等于5/4的过程.
cos方5π/12+cos方π/12+cosπ/12*cos5π/12 最后等于4/5的过程.