The sides of an acute triangle measure 2 inches, 3 inches, and 4 inches respectively. Which of the following equations, when solved for 0, gives the measure of the largest angle of the triangle?
(Note: For any triangle with sides of length a, b, and c that are opposite angles A, B and C respectively,
sin A/α = sin B/b = sin C/c and c² = α² + b²- 2αb cos C.)