sin(a+105度)cos(a-15度)-cos(a+105度)sin(a-15度)
sin(a+105度)cos(a-15度)-cos(a+105度)sin(a-15度)
sin a + cos a = m .求 sin a -cos a (0度< a
化简sin(a-15度)cos(a+15度)+cos(a-15度)sin(a+15度)
化简:[cos(a+15度)]^2+[sin(a-15度)]^2+[sin(a+180度)]*[cos(a-180度)]
4.9-1/化简:[cos(a+15度)]^2+[sin(a-15度)]^2+[sin(a+180度)]*[cos(a-
已知 cos(75度+a)=1/3 求 cos(105度-a)+sin(a-105度)
sin(a+75度)+cos(a+45度)-根号3cos(a+15)度的值
cos(27度+a)cos(33度-a)-sin(27度+a)sin(33度-a)求化简
化简 sin(a+180度)cos(-a)sin(-a-180度)
sin(a+180度)cos(-a)sin(-a-180度)化简
化简sin(360度-a)cos(1080度-a)sin(-360度-a)除以cos(a-180度)sin(900度-a
化简cos^2(a+15)+sin^2(a-15))+sin(a+180)cos(a-180)