D(f)=R
f'(x)=-6x^2-6x=-6x(x+1)
D(f')=R
f'(x)=0
-6x(x+1)=0
x=0
x=-1
1<=x<=3
f(1)=-2-3+4=-1
f(3)=-54-27+4=-77
На 1<=х<=3
fнаиб.=f(1)=-1
fнаим.=f(3)=-77
28-4(3x+2)=5(2x-7)
28-12х-8=10х-35
-12х-10х=-35-28+8
-22х=-55
х=-55/(-22)=2.5
<span>х=2.5</span>
2x^2 + 12x - 18 = 0
x^2 + 6x + 9 = 0
x1 = -3
x2 = -3