解下列不等式x²-7x+12>0,-x²-2x+3≥0x²-2x+1<0,x²-2x+2<0

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解下列不等式x²-7x+12>0,-x²-2x+3≥0x²-2x+1<0,x²-2x+2<0

解下列不等式x²-7x+12>0,-x²-2x+3≥0x²-2x+1<0,x²-2x+2<0
解下列不等式x²-7x+12>0,-x²-2x+3≥0
x²-2x+1<0,x²-2x+2<0

解下列不等式x²-7x+12>0,-x²-2x+3≥0x²-2x+1<0,x²-2x+2<0
(x-3)(x-4)>0
x小于3,或x大于4
x^2+2x-3小于等于0
(x+3)(x-1)小于等于0
-3小于等于x小于等于1

x²-7x+12>0
(x-3)(x-4)>0
则x>4或x<3;
-x²-2x+3≥0
x²+2x-3<=0
(x+3)(x-1)<=0
-3<=x<=+1

解 令Y=X2-7X+12
则其图像如下 其与X轴的交点(3,0),(4,0)
x²-7x+12>0 即Y>0
所以X<3 或X>4