Question

Алгебра 8 класс помогите плиз срочно

Answer 1

$a( \frac{a}{a - b} + \frac{a}{b} ) \div \frac{2}{2a {}^{2} - 2b {}^{2} } =\frac{a {}^{4} + a {}^{3}b }{b} \\ 1) \: \: \: \: \frac{a}{a - b} + \frac{a}{b} = \frac{ab + a(a - b)}{b(a - b)} = \frac{ab + a {}^{2} - ab}{ba - b {}^{2} } = \frac{ a {}^{2} }{ba - b {}^{2} } \\ 2)a \times \frac{a {}^{2} }{ba - b {}^{2} } = \frac{a \times a {}^{2} }{ba - b {}^{2}} = \frac{ a {}^{3} }{ ba - b {}^{2} } \\ 3) \frac{ a {}^{3} }{ ba - b {}^{2} } \div \frac{2}{2a {}^{2} - 2b {}^{2} } = \frac{ a {}^{3} }{ ba - b {}^{2} } \times \frac{2a {}^{2} - 2b {}^{2} }{2} = \frac{ a {}^{3} }{ b(a - b) } \times \frac{2(a - b)(a + b)}{2} = \frac{a {}^{3}(a + b) }{b} = \frac{a {}^{4} + a {}^{3}b }{b}$