Quiz Mathématiques 9ème : Équations, Fonctions et Géométrie

Question 1 sur 10 10:00

[{"id":50931,"question":"Quelle est la solution de l'équation 3x - 5 = 10 ?","option_a":"x = 5","option_b":"x = 15\/3","option_c":"x = 5\/3","option_d":"x = 10\/3","option_e":"","option_f":"","bonne_reponse":"A","explication":"3x - 5 = 10 → 3x = 15 → x = 5. L'équation est résolue en isolant x.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":50932,"question":"La fonction f(x) = 2x + 3 est-elle linéaire ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"B","explication":"Une fonction linéaire s'écrit f(x)=ax. Ici, f(x)=2x+3 est affine car elle contient un terme constant (b=3).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":50933,"question":"Quel est l'antécédent de 7 par la fonction f(x) = 4x - 1 ?","option_a":"x = 2","option_b":"x = 1","option_c":"x = 3","option_d":"x = 0","option_e":"","option_f":"","bonne_reponse":"A","explication":"On résout 4x - 1 = 7 → 4x = 8 → x = 2. L'antécédent de 7 est donc 2.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":50934,"question":"Dans un triangle rectangle, si les côtés de l'angle droit mesurent 3 cm et 4 cm, quelle est la longueur de l'hypoténuse ?","option_a":"5 cm","option_b":"6 cm","option_c":"7 cm","option_d":"4,5 cm","option_e":"","option_f":"","bonne_reponse":"A","explication":"D'après le théorème de Pythagore : 3² + 4² = 9 + 16 = 25 → hypoténuse = √25 = 5 cm.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":50935,"question":"L'inéquation 2x + 1 \u003E 5 a pour solution x \u003E 2.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"A","explication":"2x + 1 \u003E 5 → 2x \u003E 4 → x \u003E 2. La solution est bien x \u003E 2.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":50936,"question":"Quelle est l'image de -3 par la fonction f(x) = -2x + 1 ?","option_a":"f(-3) = 7","option_b":"f(-3) = -5","option_c":"f(-3) = 5","option_d":"f(-3) = -7","option_e":"","option_f":"","bonne_reponse":"A","explication":"f(-3) = -2*(-3) + 1 = 6 + 1 = 7. L'image de -3 est donc 7.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":50937,"question":"Un triangle rectangle a un angle de 30°. Quelle est la valeur du cosinus de cet angle ?","option_a":"√3\/2","option_b":"1\/2","option_c":"√2\/2","option_d":"1\/√3","option_e":"","option_f":"","bonne_reponse":"B","explication":"Dans un triangle rectangle, cos(30°) = √3\/2. Ici, l'angle est de 30°, donc cos(30°) = √3\/2.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":50938,"question":"L'aire d'un rectangle de longueur 5 cm et de largeur 3 cm est de 15 cm².","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"A","explication":"L'aire d'un rectangle se calcule par A = longueur × largeur = 5 × 3 = 15 cm². L'affirmation est donc vraie.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":50939,"question":"Quelle est la représentation graphique d'une fonction affine ?","option_a":"Une droite","option_b":"Une parabole","option_c":"Un cercle","option_d":"Une hyperbole","option_e":"","option_f":"","bonne_reponse":"A","explication":"Une fonction affine f(x)=ax+b se représente graphiquement par une droite dans un repère.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":50940,"question":"Résoudre l'inéquation : -x + 4 ≤ 2.","option_a":"x ≥ 2","option_b":"x ≤ 2","option_c":"x \u003E 2","option_d":"x \u003C 2","option_e":"","option_f":"","bonne_reponse":"B","explication":"-x + 4 ≤ 2 → -x ≤ -2 → x ≥ 2 (en multipliant par -1, on inverse le sens de l'inégalité).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0}]