来自何杰的问题
【已知cos(5π/12+a)=1/3,且-《a《-π/2,则cos(π/12—a)等于?是:且-π《a《-π/2】
已知cos(5π/12+a)=1/3,且-《a《-π/2,则cos(π/12—a)等于?
是:且-π《a《-π/2


【已知cos(5π/12+a)=1/3,且-《a《-π/2,则cos(π/12—a)等于?是:且-π《a《-π/2】
已知cos(5π/12+a)=1/3,且-《a《-π/2,则cos(π/12—a)等于?
是:且-π《a《-π/2
因为-π