Question

Aduceti la o froma mai simpla

Answer 1

[tex]a = \frac{3}{ \sqrt{5}-2 } - 3\sqrt{5} [/tex]

$a=3( \sqrt{5}+2)-3 \sqrt{5}$

$a=3 \sqrt{5} +6-3 \sqrt{5}$

$a = 6$

Answer 2

$a= \frac{3}{ \sqrt{5}-2}-3 \sqrt{5} = \\ \\ \frac{3( \sqrt{5}+2)}{ ( \sqrt{5}-2)( \sqrt{5}+2) }-3 \sqrt{5} } = \\ \\ \frac{3( \sqrt{5}+2)}{ 5-4}-3 \sqrt{5} } = \\ \\ 3 \sqrt{5}+6}-3 \sqrt{5}= \\ \\ =6$