Question

Dau coroana!!

1. Calculati:

a)
$3 \sqrt{98} - 2 \sqrt{72} + 5 \sqrt{8}$
b)
$\sqrt{7 - 2 \sqrt{6} }$
2. Rationalizati

$\frac{18}{ \sqrt{5 } - \sqrt{3} }$
3. Determinati valorile lui x E R pentru care are sens:
$\sqrt{100 - {x}^{2} }$
​

Answer 1

$a)7 \sqrt{2} - 12 \sqrt{2} + 5 \sqrt{8} = - 5 \sqrt{2} + 5 \sqrt{8} = 5 \sqrt{2} + 10 \sqrt{2} = 15 \sqrt{2}$

$b) \sqrt{(1 - \sqrt{6)} } {}^{2} = \sqrt{6 - 1}$