Question

Помогите даю 50 балов Алгебра 8 клас

Answer 1

Ответ:

$1)\ \ \dfrac{7a}{a+3}\ \ \ \to \ \ \ a+3\ne 0\ \ ,\ \ a\ne -3\ ,\ a\in (-\infty ;-3)\cup (-3\, ;+\infty )\\\\\dfrac{a-1}{2}\ \ \ \to \ \ \ a\in (-\infty ;+\infty )\\\\\\2)\ \ \dfrac{3x^4y}{27x^3y^3}=\dfrac{x}{9y^2}\ \ ,\ \ \ \ \dfrac{2x^2-6x}{4x}=\dfrac{2x\, (x-3)}{4x}=\dfrac{x-3}{2}\ \ ,\\\\\\\dfrac{3x+3}{x^2+2x+1}=\dfrac{3\, (x+1)}{(x+1)^2}=\dfrac{3}{x+1}\\\\\\\dfrac{27y^3+1}{1-9y^2}=\dfrac{(3y+1)(9y^2-3y+1)}{(1-3y)(1+3y)}=\dfrac{9y^2-3y+1}{1-3y}$