Question

$( \sqrt{13} - \sqrt{2} ) \sqrt{15 + 2 \sqrt{26} }$
$2 \frac{2}{3} - 5\frac{1}{2} - 2 \frac{1}{6}$
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Answer 1

1.
(√13 - √2) • √(15 + (2√26)) =
= √((√13 - √2)^2 • (15 + 2√26)) =
= √((13 - 2√26 + 2) • (15 + 2√26)) =
= √(15•13 - 15•2√26 + 15•2 + 13•2√26 -
- (2√26)•(2√26) + 2•2√26) =
= √(195 - 30√26 + 30 + 26√26 - 104 + 4√26)=
= √121 = 11
Ответ: 11.

2.
2 2/3 - 5 1/2 - 2 1/6 =
8/3 - 7/2 - 13/6 =
= 16/6 - 21/6 - 13/6 =
= (16 - 21 - 13)/6 =
= (-18)/6 = -3
Ответ: -3

Answer 2

1.

$( \sqrt{13} - \sqrt{2}) \times \sqrt{15 + 2 \sqrt{16} } = ( \sqrt{13} - \sqrt{2} ) \times \sqrt{( \sqrt{2} + \sqrt{13} )^{2} } = ( \sqrt{13} - \sqrt{2} ) \times ( \sqrt{13} + \sqrt{2} ) = \sqrt{13}^{2} - \sqrt{2}^{2} = 13 - 2 = 11$

Ответ: 11.

2.

$2 \frac{2}{3} - 5 \frac{1}{2} - 2 \frac{1}{6} = \frac{2 \times 3 + 2}{3} - \frac{5 \times 2 + 1}{2} - \frac{2 \times 6 + 1}{6} = \frac{8}{3} - \frac{11}{2} - \frac{13}{6} = \frac{16 - 33 - 13}{6} = \frac{ - 30}{6} = - 5$

Ответ: -5.