Question

Упростите :$frac{x^{2}-3x+9 }{x^{3}+27 } + frac{x-3}{x^{2}- 9 } - frac{x+5}{x+3}$

СРОЧНО!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Answer 1

$frac{x^{2}-3x+9 }{x^{3}+27 } + frac{x-3}{x^{2}- 9 } - frac{x+5}{x+3} = frac{x^{2}-3x+9 }{(x + 3)(x {}^{2} { - 3x + 9)} } + frac{x - 3}{(x - 3)(x + 3)} - frac{x + 5}{ { x + 3}{} } = frac{1}{x + 3} + frac{1}{x + 3} - frac{x + 5}{x + 3} = frac{1 + 1 - (x + 5)}{x + 3} = frac{2 - x - 5}{x + 3} = frac{ - x - 3}{x + 3} = frac{ - (x + 3)}{x + 3 } = - 1$