Respuesta :


Using the cosine rule, a² =  b² +  c² -2 bc cos θSImplifying the equation in terms of cos  theta,
cos(θ) = (a² + c² - b²)/(2bc) 
(a² + c² - b²)/(2bc) > 0 a² + c² - b² > 0 
assuming b and c are non zeros, the resulting inequality should be
a² + c² > b²

THe appicable inequality is a