Bonjour, Solve the following equations: 1) 4x^2 -1 = 0 2) 16x^2=25
Mathématiques
elephanttu
Question
Bonjour,
Solve the following equations:
1) 4x^2 -1 = 0
2) 16x^2=25
Solve the following equations:
1) 4x^2 -1 = 0
2) 16x^2=25
1 Réponse
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1. Réponse loulakar
Bonjour,
Solve the following equations:
1) 4x^2 -1 = 0
(2x - 1)(2x + 1) = 0
Un produit de facteur est nul si et seulement si au moins un de ses facteurs est nul :
2x - 1 = 0 ou 2x + 1 = 0
2x = 1 ou 2x = -1
x = 1/2 ou x = -1/2
2) 16x^2=25
16x² - 25 = 0
(4x - 5)(4x + 5) = 0
4x - 5 = 0 ou 4x + 5 = 0
4x = 5 ou 4x = -5
x = 5/4 ou x = -5/4