Question

como se faz essas expressoes?

7dc26d37392e5dc20233bc58407b2013.docx

Answer 1

$b) \\ \\ \dfrac{1 + \dfrac{a - b}{a + b}}{1 - \dfrac{a - b}{a + b}} \\ \\ \\ \dfrac{\dfrac{1*(a+b) + (a - b)}{a + b}}{\dfrac{1*(a+b) - (a -b)}{a + b}} \\ \\ \\ \dfrac{\dfrac{a+\not b + a -\not b}{a + b}}{\dfrac{\not a+b - \not a +b}{a + b}}$

$\dfrac{\dfrac{2a}{a + b}}{\dfrac{2b}{a + b}} \\ \\ \\ \dfrac{\dfrac{2a}{\not a +\not b}}{\dfrac{2b}{\not a + \nott b}} \\ \\ \\ => \dfrac{2a}{2b} => \dfrac{a}{b}$

==========

$c) \\ \\ ( \dfrac{x^2 - 4}{9x^2 - 16}) * ( \dfrac{3x + 4}{2x + 4} ) \\ \\ \\ \dfrac{(x - 2)(x + 2)}{(3x - 4)(3x + 4)} * \dfrac{3x + 4}{2(x + 2)} \\ \\ \\ \dfrac{(x - 2)(\not x + \not 2)}{(3x - 4)(\not 3x +\not 4)} * \dfrac{\not 3x + \not 4}{2(\not x +\not 2)}$

$\dfrac{(x - 2)}{(3x - 4)} * \dfrac{1}{2} \\ \\ \\=> \dfrac{x - 2}{2 * (3x - 4)}$