Question

a=$\frac{4}{ \sqrt{15} +1}$.Rationalizati numarul

Answer 1

[tex]A= \frac{4( \sqrt{15}-1) }{ (\sqrt{15}+1)(\sqrt{15}-1)} =\frac{4( \sqrt{15}-1) }{ 14}=\\ =\frac{2( \sqrt{15}-1) }{ 7}[/tex]