(х-3)(Х^2+3х+9)=х(х-8)(х+9)
X^2(x+1)-9(x+1)=0
(x^2-9)(x+1)=0
x1=3, x2=-3, x3=-1
-4³+(-0.3)³×2²=(-64-0.027)×4=(-64.027)×4=-256.108
<span>ctgx-sinx=2sin^2(x/2)</span>
ctgx-sinx=1-cosx
cosx-sin^2x+cosx*sinx-sinx=0
(1+sinx)(cosx-sinx)=0
1+sinx=0
sinx=-1
x=-п/2+2п*n
cosx-sinx=0
ctgx=1
x=arcctg1+п*k
x=п/4+п*k