Question

Va rog super repede! Dau 40de puncte si o coroana!

Answer 1

$1 . \: \: \: \: {2 \sqrt{5} . \: \sqrt{3} }$

$2. \: \: \: \\ {x}^{2} = \frac{4}{49} \\ x = \frac { + - \sqrt{4} }{ + - \sqrt{49} } \\ x = \frac{ + - 2} { + - 7} \\ x = - \frac{2}{7}$

$cd = 4cm \\ cm = cd \div 2 \\ cm = 2cm$

$3. \\ \frac{x}{ - 2} = \frac{7 \sqrt{3} }{y} \\ x \times y = - 2 \times 7 \sqrt{3} \\ n = 3xy + 42 \sqrt{3} \\ n = 3 \times ( - 14) \sqrt{3} + 42 \sqrt{3} \\ n = - 42 \sqrt{3} + 42 \sqrt{3} \\ n = 0$

$4. \: \: \: \sqrt{ {2}^{2} + {2}^{5} } = \\ = \sqrt{4 + 32} = \\ = \sqrt{36} = 6$

$5. \: \: \: \: \sqrt{ {(2 - \sqrt{5} )}^{2} } - \sqrt{ {(2 + \sqrt{5}) }^{2} } = \\ = |2 - \sqrt{5} | - |2 + \sqrt{5} | = \\ = \sqrt{5} - 2 - (2 + \sqrt{5} ) = \\ = \sqrt{5} - 2 - 2 - \sqrt{5} = \\ = - 4$

$6. \: \: \: \: {180}^{0}$

$8. \: \: \: \: aria \: rombului \: = d1 \times d2 \\ 6 \times 8 = 48 {cm}^{2}$