Odpowiedź:
4 × [tex](\sqrt{5}) ^{2}[/tex] - 5[tex]\sqrt{2}^{2}[/tex] = ?
[tex]\sqrt{5} ^{2}[/tex] = [tex]\sqrt{5}[/tex] × [tex]\sqrt{5}[/tex] = [tex]\sqrt{25}[/tex] = 5
[tex]\sqrt{2}^{2}[/tex] = [tex]\sqrt{2}[/tex] × [tex]\sqrt{2}[/tex] = [tex]\sqrt{4}[/tex] = 2
Czyli:
(4 × 5) - (5 × 2) = 20 - 10 = 10