解不等式1,(x^2-2x+a-2)/(x^2-x-2)>12,|log1/3(3-x)|-log1/3(x)>=1

热心网友

1,(x^2-2x+a-2)/(x^2-x-2)1解:两边同时减1==〉(-x+a)/(x-2)(x+1)0==〉(x-a)/(x-2)(x+1)=1 解:首先3-x0且x0,==〉x∈(0,3)当log1/3(3-x)1,x∈(0,2)时,==〉-log1/3(3-x)-log1/3(x)≥1==〉log1/3(3-x)x≤-1=log1/3(3)==〉(3-x)x≥3==〉x^2-3x+3≥0恒成立,∴x∈(0,2)当log1/3(3-x)≥0,即0<3-x≤1,x∈(2,3)时,==〉log1/3(3-x)-log1/3(x)≥1==〉log1/3[(3-x)/x]≥1=log1/3(1/3)==〉(3-x)/x≤1/3==〉9-3x≤x,∴x∈[9/4,3)综上,解集为(0,2)∪[9/4,3)