Question

8 класс пожалйста дроби

Answer 1

$2z^3-6x^5=2(z^3-3x^5) \ 4a^2- frac{1}{9} b^2=(2a- frac{1}{3} b)(2a +frac{1}{3} b) \ q^2-4q^{-5}=q^2(1-4q^{-7}) \ 9b^2-3=3(3b^2-1)$

$frac{x^2-8x+16}{x^2-16}= frac{(x-4)^2}{(x-4)(x+4)}= frac{x-4}{x+4} \ frac{16ab^4}{-56ab^3}=- frac{2b}{7} \ frac{x^2-9}{x^2-6x+9} = frac{(x-3)(x+3)}{(x-3)^2} = frac{x+3}{x-3} \ frac{3x-9y}{(3-x)(x-y)}= frac{3(x-3y)}{(3-x)(x-y)}$
$frac{3y}{4y-4} + frac{2y}{5-5y}= frac{3y}{4(y-1)} - frac{2y}{5(y-1)}=frac{15y}{20(y-1)} - frac{8y}{20(y-1)}=frac{7y}{20(y-1)}$
$4a- frac{8a^2}{2a-3} = frac{8a^2-12a-8a^2}{2a-3} =-frac{12a}{2a-3}$

$frac{3x+2}{5x}- frac{5x+3y}{10xy} - frac{y-1}{2y} = frac{6xy+4y}{10xy}- frac{5x+3y}{10xy} - frac{5xy-5x}{10xy} = \ = frac{6xy+4y-5x-3y-5xy+5x}{10xy}= frac{xy+y}{10xy}= frac{x+1}{10x}=$