Răspuns:
d)
[tex] (\sqrt{3} - 1)( \sqrt{3} + 1)[/tex]
=
[tex] \sqrt{3} ^{2} - 1 ^{2} [/tex]
=
[tex] \sqrt{9} - 1[/tex]
= 3-1
=2
e)
[tex](3 \sqrt{ 5} - 2)(3 \sqrt{5} + 2)[/tex]
=
[tex]3 \sqrt{5} ^{2} - {2}^{2} [/tex]
=3x3x5 - 4
=45 - 4
=41
Regulă: (a-b) (a+b) =
[tex] {a}^{2} - {b}^{2} [/tex]
