帮我解,证明恒等式(cos平方5π/12)+(cos平方π/12)+(cos5π/12)(cosπ/12)=5/4
帮我解,证明恒等式(cos平方5π/12)+(cos平方π/12)+(cos5π/12)(cosπ/12)=5/4
数学,证明恒等式(cos平方5π/12)+(cos平方π/12)+(cos5π/12)(cosπ/12)=5/4.
cos5/12πcosπ/12+cosπ/12sinπ/6=?
试证明:1+2sinαcosα/cos平方α-sin平方α=tan(π/4-α)
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.
化简cos(π/12)*cos(5π/12)
计算cos(a+5π/12)cos(a+π/6)+cos(π/12-a)cos(π/3-a)
证明下列恒等式: (1)2sin(2/π+x)cos(2/π-x)*cosθ+(2cos^2x-1)*sinθ=sin(
计算cos平方π/12-1/2
(sin5π/12-sinπ/12)(cos5π/12+cosπ/12)=?
g(x)=sin平方√1-cos/1+cosx+cos平方√1-sinx/1+sinx,其中x∈(π,5π/4),求函数