Решите 1.4.8 1.4.9 1.4.10

Решите задачу:

$1.4.8) \frac{78}{?}$
$1.4.8) \frac{78}{(2 \sqrt{3}) {}^{2} } = \frac{78}{4 \times 3} = \frac{78}{12} = \frac{26}{4} = \frac{13}{2} = 6 \frac{1}{2} \\ 1.4.9)2 \sqrt{19} \times 2 \sqrt{3} \times \sqrt{57} \\ 4 \sqrt{19 \times 3 \times 57} = 4 \sqrt{3249} = 4 \times 57 = 228 \\ 1.4.10)3 \sqrt{23} \times 2 \sqrt{3} \times \sqrt{69} \\ 3 \times 2 \sqrt{23 \times 3 \times 69} = 6 \sqrt{4761} = 6 \times 69 = 414$