Question

два уравнения 30 баллов​

Answer 1

а) $\dfrac{a^2-(b^2-2bc+c^2)}{b^2-(a^2+2ac+c^2)}=\dfrac{a^2-(b-c)^2}{b^2-(a+c)^2}=$

$=\dfrac{(a-(b-c))(a+(b-c))}{b-(a+c))(b+a+c)}=\dfrac{(a-b+c)(a+b-c)}{(b-a-c)(b+a+c)}=\\ =-\dfrac{a+b-c}{a+b+c}=\dfrac{c-a-b}{a+b+c}.$

б) $\dfrac{x^n(x^2-4x+4)}{x^2-6x^2+12x-8}=\dfrac{x^n(x-2)^2}{(x-2)^3}=\dfrac{x^n}{x-2}.$