1/2
Объяснение:
sin(α)·cos(β) = ½(sin(α+β) + sin(α-β))
1/2*(sin174+sin150)+1/2*(sin30+sin(-6))
(sin174)/2+1/2-(sin6)/2
1/2*2*cos90*sin84+1/2
0+1/2=1/2
ответ: V3 /2
sin162=sin(180-18)=sin18, тогда,
=sin18*cos12+sin12*cos18=sin(18+12)=sin30=1/2
б) =cos(p/30-p/15) /sin(7p/30 +sin 4p/15)=cos(-p/30) /sin(15p/30)=
V3/2 /sin p/2 =V3/2 /1 =V3/2 (V-корень)
1/2
Объяснение:
sin(α)·cos(β) = ½(sin(α+β) + sin(α-β))
1/2*(sin174+sin150)+1/2*(sin30+sin(-6))
(sin174)/2+1/2-(sin6)/2
1/2*2*cos90*sin84+1/2
0+1/2=1/2
ответ: V3 /2
Объяснение:
sin162=sin(180-18)=sin18, тогда,
=sin18*cos12+sin12*cos18=sin(18+12)=sin30=1/2
б) =cos(p/30-p/15) /sin(7p/30 +sin 4p/15)=cos(-p/30) /sin(15p/30)=
V3/2 /sin p/2 =V3/2 /1 =V3/2 (V-корень)