12*(-3/4)-3(5/6)=-9-2,5=-11,5
a)5a+7b-2a-8b=3a-b
b) 3(4x+2) - 5= 12x+6-5=12x+1
c) 20b-(b-3)+(3b-10)=20b-b+3+3b-10=22b-7
(x -3)²/8 -(x -2)²/2 =1 -x
((x²-6x+9) -4*(x -2)²)/8 =1 -x
x²-6x+9 -4(x²-4x+4) =8*(1 -x)
x²-6x+9 -4x²+16x -16 =8x -8
-3x² +10x -7 -8x +8 =0
-3x² +2x +1 =0, *(-1)
3x² -2x -1 =0
D=b² -4ac(a=3,b= -2,c= -1)
D=4 +12 =16 =4²
x1,x2 =(-b+-vD)/2a
x1 =(2 -4)/6 = -2/6= -1/3
x2 =(2 +4)/6 =1
ответ: x= -1/3, x =1
X в квадрате -3х=0
х выносим за скобку
х(х-3)=0 и каждый множитель приравниваем нулю. х=0 и х-3=0
х=3
![y^3-6+11y-6y^2=y^3-6+11y-6y^2+y-y=\\\\(y^3-y)-(6-12y+6y^2)=\\\\(y*y^2-y*1)-(6*1-6*2y+6*y^2)=\\\\y(y^2-1)-6(1-2y+y^2)=\\\\y(y^2-1^2)-6(1^2-2*1*y+y^2)=\\\\y(y-1)(y+1)-6(y-1)^2=\\\\(y-1)(y^2+y)-(y-1)(6y-6)=\\\\(y-1)((y^2+y)-(6y-6))=\\\\(y-1)(y^2+y-6y+6)=\\\\(y-1)(y^2-5y+6)=\\\\(y-1)(y^2-2y-3y+6)=\\\\(y-1)((y^2-2y)-(3y-6))=\\\\(y-1)(y(y-2)-3(y-2))=\\\\(y-1)(y-2)(y-3)](https://tex.z-dn.net/?f=y%5E3-6%2B11y-6y%5E2%3Dy%5E3-6%2B11y-6y%5E2%2By-y%3D%5C%5C%5C%5C%28y%5E3-y%29-%286-12y%2B6y%5E2%29%3D%5C%5C%5C%5C%28y%2Ay%5E2-y%2A1%29-%286%2A1-6%2A2y%2B6%2Ay%5E2%29%3D%5C%5C%5C%5Cy%28y%5E2-1%29-6%281-2y%2By%5E2%29%3D%5C%5C%5C%5Cy%28y%5E2-1%5E2%29-6%281%5E2-2%2A1%2Ay%2By%5E2%29%3D%5C%5C%5C%5Cy%28y-1%29%28y%2B1%29-6%28y-1%29%5E2%3D%5C%5C%5C%5C%28y-1%29%28y%5E2%2By%29-%28y-1%29%286y-6%29%3D%5C%5C%5C%5C%28y-1%29%28%28y%5E2%2By%29-%286y-6%29%29%3D%5C%5C%5C%5C%28y-1%29%28y%5E2%2By-6y%2B6%29%3D%5C%5C%5C%5C%28y-1%29%28y%5E2-5y%2B6%29%3D%5C%5C%5C%5C%28y-1%29%28y%5E2-2y-3y%2B6%29%3D%5C%5C%5C%5C%28y-1%29%28%28y%5E2-2y%29-%283y-6%29%29%3D%5C%5C%5C%5C%28y-1%29%28y%28y-2%29-3%28y-2%29%29%3D%5C%5C%5C%5C%28y-1%29%28y-2%29%28y-3%29)
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