D=b^2-4*a*c=4-16=-12
х1=4-(-12)/8= -16/8=-2
х2=4+(-12)/8=-8/8=-1
Sin(x-6)=0
т.к. sin(t)=0 при t=πn
x-6=πn
x=6+πn
cos(π-6x)=0
т.к. cos(π-t)=-cos(t)
-cos(6x)=0 | *(-1)
cos(6x)=0
т.к. cos(t)=0 при t=π/2+πn
6x=π/2+πn
x=π/12+(πn)/2
tgx=-9,63
одз: x≠π/2+πn
tgx=-963/100
x=arctg(-963/100)+πn
<span>Tg(x/5)=12/5
одз: x</span>≠(5π)/2+5πn
x/5=arctg(12/5)
x=5arctg(12/5)+5πn
для всех значений n ∈ Z
<span>cos14п\3=cos2π/3=-cosπ/3=-1/2
</span>sin25п\6=sinπ/6=1/2
<span>tg17п\4=tgπ/4=1
4*(-1/2)-1/2+1=-2-1/2+1=-1 1/2
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