4cos3x+3sin3x=5sin(3x+t) t=arcsin(4/5)
5sin(3x+arcsin(4/5)=5
sin(3x+arcsin(4/5)=1
3x+arcsin4/5=pi/2+2pik
3x=pi/2-arcsin4/5+2pik
x=pi/6-arcsin(4/5)/3+2pik/3
U+v=4
3u-5v=20
u=4-v
3(4-v)-5v=20,12-3v-5v=20,12-8v=20,8v=12-20,8v=-8,v=-1
u=4-v
v=-1
u=4-(-1)=4+1=5
v=-1
/u,v/=/5,-1/
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-П/30+2П*2/30=-П/30+4П/30=3П/30=П/10=18°
-П/30 + 2П *3/30=-П/30+6П/30=5П/30=П/6=30°
<span>-П/30 + 2П * 4/30=-П/30+8П/30=7П/30
</span>
<span>-П/30 + 2П * 5/30=-П/30+10П/30=9П/30=3П/10</span>