Question

Introduceți factorul sub radical 4 radical din 15
$2 \sqrt{17}$
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Answer 1

$4 \sqrt{15} = \sqrt{4 {}^{2} \times 15 } = \sqrt{16 \times 15} = \sqrt{240} \\ \\ \\ 2 \sqrt{17} = \sqrt{2{}^{2} \times 17} = \sqrt{4 \times 17} = \sqrt{68}$