Question

ajutatima va rog e foarte urgent corona si inma doar c,e,f​

Answer 1

$c) \sqrt{6} \times ( \sqrt{6} - \sqrt{3} ) = \\ = \sqrt{6 \times 6} - \sqrt{6 \times 3} = \\ = \sqrt{6 {}^{2} } - \sqrt{2\times 3 \times 3} = \\ = 6 - \sqrt{2 \times 3 {}^{2} } = \\ = 6 - 3 \sqrt{2}$

$e) \sqrt{3} ( \sqrt{3} - \sqrt{27} + 5) = \\ = \sqrt{3 \times 3} - \sqrt{27 \times 3} +5 \sqrt{3} = \\ = \sqrt{3 {}^{2} } - \sqrt{3 \times 3 \times 3 \times 3} + 5 \sqrt{3} = \\ = 3 - \sqrt{3 {}^{4} } + 5 \sqrt{3} = \\ = 3 - 3 {}^{2} + 5 \sqrt{3} = \\ = 3 - 9 + 5 \sqrt{3} = \\ = - 6 + 5 \sqrt{3}$

$f) \sqrt{7} \times ( \sqrt{2} - \sqrt{3} ) = \\ = \sqrt{7 \times 2} - \sqrt{7 \times 3} = \\ = \sqrt{14} - \sqrt{21}$