Question

$( frac{1}{x + 3} - frac{27}{ {x}^{2} + 27 } + frac{9}{ {x}^{2} - 3a + 9 }) times (x - frac{6x - 9}{x + 3} )$
8 класс
решите пж

Answer 1

$displaystyle tt {} bigg(frac{1}{x+3}- frac{27}{x^{3}+27}+ frac{9}{x^{2}-3x+9}bigg)cdotbigg(x- frac{6x-9}{x+3}bigg)=\\\=frac{x^{2}-3x+9-27+9x+27}{(x+3)(x^{2}-3x+9)}cdot frac{x^{2}+3x-6x+9}{x+3}=\\\=frac{x^{2}+6x+9}{(x+3)(x^{2}-3x+9)}cdot frac{x^{2}-3x+9}{x+3}=frac{(x+3)^{2}}{(x+3)^{2}}=1;$