Pt ⇔\(\dfrac{1}{sinx.cosx}=\dfrac{1}{2sin\left(x+\dfrac{\pi}{3}\right)}\)
⇔ sinx.cosx = 2sin\(\left(x+\dfrac{\pi}{3}\right)\)
⇔ \(\dfrac{1}{2}\)sin2x = 2sin\(\left(x+\dfrac{\pi}{3}\right)\)
⇔ sin2x = 4sin\(\left(x+\dfrac{\pi}{3}\right)\)
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