Ответ на пример: х=2 82/85.
<span>6 cos в квадрате +5cos+1=0
6</span> cos²<span>x +5cosx+1=0
6t</span>²+5t+1=0
t1=[-5-√(25-24)]/12=-1/2 cosx =-1/2 x1=π-π/3+2πn=2π/3+2πn, n∈Z
x2=-(π-π/3)+2πn=-2π/3+2πn, n∈Z
t2=[-5+√(25-24)]/12=-1/3 cosx =-1/2 x1=π-arccos(1/3)+2πn, n∈Z
x2=-(π-arccos(1/3))+2πn, n∈Z
428000-(х+28234)=243146
Х+28234=428000-243146
Х+28234=184854
Х=184854-28234
Х=156620
1786:47=38
<span>7995:65=123
4440:20=222
211*9=1899
6120:51=120</span>