Номер 1.

1) 2√2 + √50 - √32 = 2√2 + √25 × 2 - √16 × 2 = 2√2 + 5√2 - 4√2 = 3√2

2) √5(√5 - √20) = √5 × √5 - √5 × √20 = √5² - √100 = 5 - 10 = - 5

3) (√3 + √2)² = √3² + 2 × √3 × √2 + √2² = 3 + 2√6 + 2 = 5 + 2√6

Номер 2.

6√2 = √36 × 2 = √72

√72 > √70

6√2 > √70

Номер 3.

1)

[tex] \frac{6 - {x}^{2} }{ \sqrt{6} - x } = \frac{( \sqrt{6} - x)( \sqrt{6} + x) }{ \sqrt{6} - x} = \sqrt{6} + x[/tex]

2)

[tex] \frac{5 - \sqrt{5} }{ \sqrt{10} - \sqrt{2} } = \frac{5 - \sqrt{5} }{ \sqrt{10} - \sqrt{2} } \times \frac{ \sqrt{10} + \sqrt{2} }{ \sqrt{10} + \sqrt{2} } = \\ = \frac{(5 - \sqrt{5})( \sqrt{10} + \sqrt{2} ) }{( \sqrt{10} - \sqrt{2} )( \sqrt{10} + \sqrt{2}) } = \frac{5 \sqrt{10} + 5 \sqrt{2} - \sqrt{50} - \sqrt{10} }{10 - 2} = \frac{5 \sqrt{10} + 5 \sqrt{2} - 5 \sqrt{2} - \sqrt{10} }{8} = \frac{4 \sqrt{10} }{8} = \frac{ \sqrt{10} }{2} [/tex]