1
ctgx=-√3/3
x=2π/3+πn,n∈z
2
sinx-2cosx=0/cosx
tgx-2=0
tgx=2
x=arctg2+πn,n∈z
180°-85°=95° размер второго угла
7c/(c+2) -(c-8)/3(c+2) * 84/c(c-8)=7c/(c+2) - 28/c(c+2)=(7c²-28)/c(c+2)=
=7(c-2)(c+2)/c(c+2)=7(c-2)/c=(7c-14)/c
<span>х^4+6х^3=0
x^3(x+6)=0
x=0 или х+6=0 х=-6
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