Question

Номер 9, помогите плиз

Answer 1

$\sqrt{27 - 8 \sqrt{11} } = \sqrt{16 + 11 - 8 \sqrt{11} } = \sqrt{{(4 - \sqrt{11 }) }^{2} } = 4 - \sqrt{11} \\ \frac{5}{4 + \sqrt{11} } = \frac{5 \times (4 - \sqrt{11} )}{16 - 11} = 4 - \sqrt{11} \\ \sqrt{27 - 8 \sqrt{11} } = \frac{5}{4 + \sqrt{11} } \\ f(27 - 8 \sqrt{11} ) = g(4 + \sqrt{11} )$