sinA=5根号3/14,A=?
sinA=5根号3/14,A=?
sina+cosa=-3/根号5,且|Sina|>|cos a|,求tan(a/2)
已知a为锐角,切sina+cosa=根号5/2,求sina*cosa的值
已知a为锐角,且sina+cosa=根号5/2,球sina.cosa
cos(a+派/6)-sina=3根号3/5,则cos(a+派/3)=?
sin(a+π/3)+sina= - 4根号3/5,则cos(a+2π/3)
sin (a+兀/3)+sina=-4根号3/5,求cos a
COS(A-30度)+SINA=4/5 乘根号3 求SIN(A+210度)?
已知sinA+sinA=根号2/3(A在90度到180度之间),求(1)sinA-cosA.(2)sinA的三次-cos
2cosa+sina =根号5,求sina,cosa
已知sina+cosa=根号3/2 求sina-cosa
已知sin(a+π/3)+sina=-(4倍根号下3)/5,-π/2