1) = 2,4х-8,4-2х+0,4=0,4х-8; при х= 4 1/6
4/10 * 25/6 = 100/60=10/6=5/3=1 2/3
2) = -3х+9-6х-8=-9х+1; при х=-2/3
-9 * (-2/3) +1= 6+1=7
3) = 2а-24-14а+21=-12а-3; при а=1/3
-12 * 1/3 -3=-4-3=-7
<span>(2/3)*x^2+2x-12 домножить на 3
2x^2+6x-36=(x+6)(x-3)
x1+x2=-6
x1-x2=-72
x1=-12/2=-6
x2=6/2=3
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Cos(a)+cos(b)=2*cos((a+b)/2)*cos((a-b)/2)