1)(x²+ax-2)/(x²-x+1)>-3
(x²+ax-2+3x²-3x+3)/(x²-x+1)>0
x²-x+1>0 при любом х,т.к.D<0⇒4x²+x(a-3)+1>0
D=a²-6a+9-16=a²-6a-7>0
a1+a2=6 U a1*a2=-7
a1=-1 U a2=7
a<-1 U a>7
2)(x²+ax-2)/(x²-x+1)<2
(x²+ax-2-2x²+2x-2)/(x²-x+1)<0
-x²+x(a+2)-4<0
x²-x(a+2)+4>0
D=a²+4a+4-16=a²+4a-12>0
a1+a2=-4 U a1+a2=-12
a1=-6 U a2=2
a<-6 U a>2
a∈(-∞;-6) U (7;∞)
3^(2-LOG3^5)+(1\3)^LOG3 5= 3^2 / 3^(log(3)5)+1/(3^log(3)5)=9/5+1/5=2
9^(3-log(3)54)+7^(-log(7)2)= 9^3/ (3^log(3)54)^2+7^(-log(7)2) =1/4+1/7^(log(7)2)=1/4+1/2=3/4
((x+y)/x-2x/(x-y))×((y-x)/(x²+y²))=((x+y)(x-y)-2x²)/(x*(x-y))×((y-x)/(x²+y²))=
=((x²-y²-2x²)/(x*(x-y))×((y-x)/(x²+y²))=((-x²-y²)/(x*(x-y))×((y-x)/(x²+y²))=
=((x²+y²)/(x*(y-x))×((y-x)/(x²+y²))≡1/x.
a) -2x^5y² * 3xy^4=-6x^6y^6
b) (-4x²y³)²=-4x^4y^6
3(2a+c)*(a-c)
(6a+3c)*(a-c)
6a^2-6ac+3ac-3c^2
6a^2-3ac-3c^2