Question

2. выполняй трюки: a2+a2 a) az-d2 - d d d-a a+d -- b) 2у 2xy² xy3 3x-y '9x²-y2 3х+у
помогите поставлю 100​

Answer 1

а)

$\frac{ {a}^{2} + {d}^{2} }{ {a}^{2} - {d}^{2} } - \frac{d}{d - a} - \frac{d}{a + d} = \\ = \frac{ {a}^{2} + {d}^{2} }{(a - d)(a + d)} + \frac{d}{a - d} - \frac{d}{a + d} = \\ = \frac{ {a}^{2} + {d}^{2} + d(a + d) - d(a - d) }{(a - d)(a + d)} = \\ = \frac{ {a}^{2} + {d}^{2} + ad + {d}^{2} - ad + {d}^{2} }{(a - d)(a + d)} = \frac{ {a}^{2} + 3 {d}^{2} }{ {a}^{2} - {d}^{2} }$

b)

$\frac{2xy {}^{2} }{3x - y} \div \frac{x {y}^{3} }{9 {x}^{2} - {y}^{2} } \times \frac{2y}{3x + y} = \frac{2x {y}^{2}(3x - y)(3x + y) \times 2y }{(3x - y) \times x {y}^{3}(3x + y) } = \\ = 2 \times 2 = 4$