Question

решите пожалуйста с объяснения 50 баллов ​

Answer 1

Ответ:

Объяснение:

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Answer 2

Задание 1

г)

$\frac{n}{m^2-n^2} - \frac{m}{m^2-m} = \frac{n}{m^2-n^2} - \frac{m}{m(m-1)} = \frac{n}{m^2-n^2} - \frac{1}{m-1} = \frac{n\cdot(m-1) - m^2 + n^2}{(m^2-n^2)(m-1)} = \\\\\frac{mn - n - m^2 + n^2}{(m^2-n^2)(m-1)}$

ж) $\frac{5a - 10b}{7b^4} \cdot \frac{14b^2}{a-2b} = \frac{5(a-2b)\cdot 14b^2}{7b^4\cdot (a-2b)} = \frac{10}{b^2}$

з) $\frac{a+2b}{a^2b^5} : \frac{a^2-4b^2}{ab^4} = \frac{(a+2b)\cdot ab^4}{a^2b^5\cdot (a-2b)(a+2b)} = \frac{a+2b}{ab(a-2b)}$

Задание 2

а) $\frac{3m^2 - m}{6m+2} \cdot \frac{7m}{3m - 1} - \frac{3m}{m+1} = \frac{m(3m-1)\cdot 7m}{2(3m+1)\cdot(3m-1)} - \frac{3m}{m+1} = \frac{7m^2}{6m + 2} - \frac{3m}{m+1} = \frac{7m^2(m+1) - 3m(6m+2)}{(6m+2)(m+1)} = \\\\ \frac{7m^3 + 7m^2 - 18m^2 - 6m}{6m^2+6m + 2m + 2} = \frac{7m^3 - 11m^2 - 6m}{6m^2 + 8m + 2}$

б)

$(\frac{2-x}{2+x} + \frac{2+x}{2-x} ):\frac{x^2+4}{x^2-4} = (\frac{4-4x+x^2+4 + 4x + x^2}{4-x^2}) : \frac{x^2+4}{x^2-4} = \frac{2x^2+8}{4-x^2} : \frac{x^2+4}{x^2-4} = \frac{2(x^2+4)\cdot (x^2-4)}{(4 - x^2)(x^2+4)} = \\\\-2$