Question

Rationalizati numitorii : 20 supra 2 radical 5 , 30 supra 2 radical 5 , 35 supra radical 5 , 30 supra radical 50

Answer 1

Răspuns:

$\frac{20}{2 \sqrt{5} } o \: amplifici \: cu \: \sqrt{5 } = > \frac{20 \sqrt{5} }{2 \times 5} = \frac{20 \sqrt{5} }{10} = 2 \sqrt{5}$

$\frac{30}{2 \sqrt{5} } o \: amplifici \: cu \: \sqrt{5} = > \frac{30 \sqrt{5} }{2 \times 5} = \frac{30 \sqrt{5} }{10} = 3 \sqrt{5}$

$\frac{35}{ \sqrt{5} } o \: amplifici \: cu \: \sqrt{5} = > \frac{35 \sqrt{5} }{5} = 7 \sqrt{5}$

$\frac{30}{ \sqrt{50} } = \frac{30}{5 \sqrt{2} } o \: amplifici \: cu \: \sqrt{2} = > \frac{30 \sqrt{2} }{5 \times 2} = \frac{30 \sqrt{2} }{10} = 3 \sqrt{2}$