алгебраические дроби 7 класс тест

Ответ от Eugene Greek[гуру]
=b(5-6a)/3ab-3a*(1-2b)/3ab=(5b-6ab-3a+6ab)/3ab=(5b-3a)/3ab
=2x/(5*(x-2))*(x-2)/3=2x/15
=(a-b)*3a^2/((a-b)*(a+b))=3a^2/(a+b)
=14n/(n-3)+12n/(3-n)^2*5(3-n)/4=14n/(n-3)+15n/(3-n)=14n/(n-3)-15n/(n-3)=-n/(n-3)
=(x/(x-y)+2xy/(x-y)^2)*(2x-x-y)/(x+y)=(x*(x-y)+2xy)/(x-y)^2*(x-y)/(x+y)=(x^2-xy+2xy)/((x-y)*(x+y))=(x^2+xy)/((x-y)*(x+y))=x*(x+y)/((x-y)*(x+y))=x/(x-y)
-2/(-2+1)=2
(x^2+4x+4)/2-(x^2-4)/4-(x^2-4x+4)/8=x^2/8*8
4(x^2+4x+4)-2(x^2-4)-(x^2-4x+4)=x^2
4x^2+16x+16-2x^2+8-x^2+4x-4-x^2=0
20x+20=0
x+1=0
x=-1