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Saitama
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Homework Statement
In a triangle ABC, with usual notation, if ##a^2b^2c^2 (\sin 2A + \sin 2B + \sin 2C) = λ(∆)^x## where ∆ is the area of the triangle and x ##\in## Q, find (λx).
Homework Equations
The Attempt at a Solution
The usual notation is:
a,b,c are three sides of the triangle opposite to the angles A,B and C respectively.
I remember a formula relating ∆ and the three sides i.e
$$\Delta=\frac{abc}{4R} \Rightarrow abc=4R \Delta$$
Also, from the law of sines,
$$\frac{a}{\sin A}=\frac{b}{\sin B}=\frac{c}{\sin C}=2R$$
where R is the circumradius of triangle.
The given expression can be written as:
$$2a^2b^2c^2 (\sin A \cos A + \sin B \cos B + \sin C \cos C)$$
I can substitute abc and sines from the above two relations but what should I replace cosines with? Law of cosines doesn't seem to be of much help.
Any help is appreciated. Thanks!