Question

(√15-3)(3√5+4√3)(√5-√3)
0,125-(9 supra √3- 2√3) :8 supra √3
Dau coroana! Va rogg! E urgent!

Answer 1

cred ca e asa.....................

Answer 2

$a) \\ \\ ( \sqrt{15} - 3)(3 \sqrt{5} + 4 \sqrt{3})( \sqrt{5} - \sqrt{3}) = (15 \sqrt{3} + 12 \sqrt{5} - 9 \sqrt{5} - 12 \sqrt{3})( \sqrt{5} - \sqrt{3}) = ((15 \sqrt{3} - 12 \sqrt{3}) + (12 \sqrt{5} - 9 \sqrt{5}))( \sqrt{5} - \sqrt{3}) = (3 \sqrt{3} + 3 \sqrt{5})( \sqrt{5} - \sqrt{3}) = 3 \sqrt{15} - 9 + 15 - 3 \sqrt{15} = (3 \sqrt{15} - 3 \sqrt{15}) + ( - 9 + 15) = 6$

$b) \\ \\ 0,125 - ( \frac{9}{ \sqrt{3} } - 2 \sqrt{3}) : \frac{8}{ \sqrt{3} } = \frac{1}{8} - (3 \sqrt{3} - 2 \sqrt{3}) \times \frac{ \sqrt{3} }{8} = \frac{1}{8} - \sqrt{3} \times \frac{ \sqrt{3} }{8} = \frac{1}{8} - \frac{3}{8} = \frac{1 - 3}{8} = \frac{ - 2}{8} = - \frac{2}{8} = - \frac{1}{4}$