Question

помогите пожалуйста

Answer 1

a)

$d = 3 \sqrt{14} \: \: \: \: \: \: \: \: \: c = 5 \sqrt{6} \\ 3 \sqrt{14} < 5 \sqrt{6} \\ \sqrt{ {3}^{2} \times 14} < \sqrt{ {5}^{2} \times 6} \\ \sqrt{9 \times 14} < \sqrt{25 \times 6} \\ \sqrt{126} < \sqrt{150} \\ 126 < 150$

б)

$a = \sqrt{4.9} \: \: \: \: \: \: \: \: \: \: \: \: \: b = \sqrt{810} \\ a \times b = \sqrt{4.9} \times \sqrt{810} = \sqrt{4.9 \times 810} = \sqrt{49 \times 81} = \\ = \sqrt{ {7}^{2} \times {9}^{2} } = 7 \times 9 = 63$