Exercice 2
Question
Déterminer les valeurs exactes des nombres suivants :
\(\sqrt{7^2 + 3^2}\)
\(\sqrt{169 \times 144}\)
\(\sqrt{169} - \sqrt{144}\)
\(\sqrt{169 - 144}\)
Indice
Carrés parfaits : En mathématiques, un carré parfait est le carré d'un entier.
0² = 0 | 1² = 1 | 2² = 4 | 3² = 9 | 4² = 16 |
5² = 25 | 6² = 36 | 7² = 49 | 8² = 64 | 9² = 81 |
10² = 100 | 11² = 121 | 12² = 144 | 13² = 169 | 14² = 196 |
Solution
Question 1
\(\sqrt{7^2 + 3^2} = \sqrt{49 + 9} = \color{red}\sqrt{58}\)
Question 2
\(\sqrt{169 \times 144} = \sqrt{13^2 \times 12^2} = \sqrt{13^2} \times \sqrt{12^2} = 13 \times 12 = \color{red}156\)
Question 3
\(\sqrt{169} - \sqrt{144} = \sqrt{13^2} - \sqrt{12^2} = 13 - 12 = \color{red}1\)
Question 4
\(\sqrt{169 - 144} = \sqrt{25} = \sqrt{5^2} = \color{red}5\)