求cos(pai)/9cos(2pai)/9cos(3pai)/9cos(4pai)/9的值(请写过程)
cos(pai/15)×cos(2pai/15)×cos(3pai/15)×cos(4pai/15)×cos(5pai/
已知:cos(x-pai/4)=根号2/10,x属于pai/2,3pai/4,求sin(2x+pai/3)的值
已知cos(3pai/2-a)=2根号5/5,a属于(pai,3pai/2) 求tan(pai/4+2a)的值
已知:cos(x-pai/4)=根号2/10,x属于pai/2,3pai/4,求sinx值
[tan(pai-a)cos(2pai-a)sin(-a+3pai/2)]/[cos(-a-pai)sin(-pai-a
已知cos(pai/2+a)=1/3,则cos(pai+2a)的值为?
已知tanatan(a+pai/3)=2,求cos(2a+pai/3)的值.
sin(pai-a)cos(-8pai-a)=60/169且a属于(pai/4,pai/2)求cosa,sina
化简:[cos(a+pai)*sin^2(a+pai)]/[tan^2(pai+a)*cos^3a]
已知cos(x-pai/4)=根号2/10,x€(pai/2,3pai/4).(1)求sinx的值(2)求sin(2x+
f(a)=[sin(pai-a)cos(2pai-a)tan(-a+3pai/2)]/[cos(-pai-a)]则f(-
已知sin(x-pai/4)=根号2/10,X属于(pai,5pai/4) 求sinx得值.求cos(2x-pai/6)