52 - (6у + 4) : 37 = 50
(6у + 4) : 37 = 52 - 50
6у + 4 = 2 * 37
6у + 4 = 74
6у = 74 -4
6у = 70
у = 11 2/3
---------------------------------
Проверка:
52 - ( 70 + 4) : 37 = 50
52 - 74 : 37 = 50
52 - 2 = 50
50 = 50
<span>cos80*1/2(cos60-cos160)=cos80*1/2(1/2+cos20)=1/4cos80+1/2cos80cos20=
=1/4cos80+1/2*1/2(cos60+cos100)=1/4cos80+1/4*1/2+1/4cos100=
=1/4sin10+1/8-1/4sin10=1/8</span>
232-(n+49)=232-n-49=232-49-n=183-n
1) x=-1; x=1
2)x € 0
3)x=-6; x=6
4)
5)x=-3/2; x=3/2