Question

Помогите, ПОЖАЛУЙСТА!!

Answer 1

1)

$\sqrt{25} = \sqrt{ {5}^{2} } = 5$

$\sqrt{36} - 4 \sqrt{81} = \sqrt{ {6}^{2} } - 4 \sqrt{ {9}^{2} } = \\ 6 - 4 \times 9 = 6 - 36 = - 30$

$\sqrt{ \frac{225}{121} } = \sqrt{ \frac{ {15}^{2} }{ {11}^{2} } } = \frac{15}{11} = 1 \frac{4}{11}$

2)

$3 \sqrt{4} + 5 \sqrt{36} = 3 \sqrt{ {2}^{2} } + 5 \sqrt{ {6}^{2} } = \\ 3 \times 2+ 5 \times 6 = 6 + 30 = 36$

$9 \sqrt{ \frac{121}{81} } - 4 \sqrt{ \frac{25}{4} } = 9 \sqrt{ \frac{ {11}^{2} }{ {9}^{2} } } - 4 \sqrt{ \frac{ {5}^{2} }{ {2}^{2} } } = \\ 9 \times \frac{11}{9} - 4 \times \frac{5}{2} = 11 - 10 = 1$

$\sqrt{ {28}^{2} - {8}^{2} } = \sqrt{(28 - 8)(28 + 8)} = \\ \sqrt{20 \times 36} = \sqrt{5 \times {2}^{2} \times {6}^{2} } = 12 \sqrt{5}$

3)

$\sqrt{28} = \sqrt{4 \times 7} = \sqrt{ {2}^{2} \times 7} = 2 \sqrt{7}$

$\sqrt{180} = \sqrt{4 \times 9 \times 5} = \\ \sqrt{5 \times {2}^{2} \times {3}^{2} } = 6 \sqrt{5}$

$\sqrt{600} = \sqrt{100 \times 6} = \sqrt{ {10}^{2} \times 6} = \\ 10 \sqrt{6}$