Can you prove this trigonometric identity?

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The trigonometric identity $\dfrac{1+\sin 6^{\circ}+\cos 12^{\circ}}{\cos 6^{\circ}+\sin 12^{\circ}}=\sqrt{3}$ has been successfully proven by forum members laura123 and kaliprasad, each employing distinct methods. Both solutions highlight the importance of manipulating trigonometric functions and utilizing known identities to arrive at the conclusion. Their approaches provide valuable insights into solving complex trigonometric equations effectively.

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Prove that $\dfrac{1+\sin 6^{\circ}+\cos 12^{\circ}}{\cos 6^{\circ}+\sin 12^{\circ}}=\sqrt{3} $.

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Congratulations to the following members for their correct solutions::)

1. laura123
2. kaliprasad

I'll show both solutions since they are different in the method of approaching.(Yes)

Here's laura123's solution:
Since $\cos 36°=\dfrac{\sqrt{5}+1}{4}$ and $\sin 18°=\dfrac{\sqrt{5}-1}{4}$ it follows:
$\cos 36°-\sin 18°=\dfrac{1}{2}$
$\cos (30°+6°)-\sin (30°-12°)=\dfrac{1}{2}$
$\cos 30°\cos 6°-\sin 30°\sin 6°-\sin 30°\cos 12°+\cos 30°\sin 12°=\dfrac{1}{2}$
$\dfrac{\sqrt{3}}{2}\cos 6°-\dfrac{1}{2}\sin 6°-\dfrac{1}{2}\cos 12°+\dfrac{\sqrt{3}}{2}\sin 12°=\dfrac{1}{2}$
$\sqrt{3}\cos 6°-\sin 6°-\cos 12°+\sqrt{3}\sin 12°=1$
$\sqrt{3}\cos 6°+\sqrt{3}\sin 12°=1+\sin 6°+\cos 12°$
$\sqrt{3}(\cos 6°+\sin 12°)=1+\sin 6°+\cos 12°$
$\dfrac{\sqrt{3}(\cos 6°+\sin 12°)}{\cos 6°+\sin 12°}=\dfrac{1+\sin 6°+\cos 12°}{\cos 6°+\sin 12°}$
$\sqrt{3}=\dfrac{1+\sin 6°+\cos 12°}{\cos 6°+\sin 12°}$.

Here's kaliprasad's solution:
First, note that

$\cos(36^\circ) - \cos(72^\circ)$
= $2 * \sin(18^\circ) * \sin(54^\circ)$
= $\dfrac{1}{2} * \dfrac{\sin(2*18)^\circ * \sin(2*54)^\circ }{\cos(18)^\circ * \cos(54)^\circ}$
= $\dfrac{1}{2} * \dfrac{\sin(36^\circ) * \sin(108^\circ)}{ (\sin(108^\circ) * \sin(36^\circ)})$
= $\dfrac{1}{2}$

We then have
$1+ \sin\ 6^\circ + \cos \ 12^\circ$
= $2(\dfrac{1}{2} +\dfrac{1}{2} \sin\ 6^\circ + \dfrac{1}{2}\cos \ 12^\circ)$
= $2(\dfrac{1}{2} +\cos \ 60^\circ \sin\ 6^\circ + \cos \ 60^\circ\cos \ 12^\circ)$
= $2 ( \dfrac{1}{2}- \sin (60-6)^\circ + \sin 60^\circ \cos 6^\circ + \cos 72^\circ + \sin 60^\circ \sin 12^\circ )$
= $2 ( \dfrac{1}{2}- \sin\ 54^\circ + \sin 60^\circ \cos 6^\circ + \cos 72^\circ + \sin 60^\circ \sin 12^\circ )$
= $2 ( \sin 60^\circ (\cos 6^\circ + \sin 12^\circ ) + \dfrac{1}{2} + \cos 72^\circ - \cos 36^\circ )$
=$2 ( \sin 60^\circ (\cos 6^\circ + \sin 12^\circ ) + \dfrac{1}{2} -( \cos 36^\circ-\cos 72^\circ )$
=$2 ( \sin 60^\circ (\cos 6^\circ + \sin 12^\circ ) + \dfrac{1}{2} -\dfrac{1}{2}$
= $2 \sin 60^\circ ( \cos 6^\circ + \sin 12^\circ )$
= $\dfrac{ 1 + \sin 6^\circ + \cos 12^\circ }{\cos 6^\circ + \sin 12^\circ } = 2 \sin 60^\circ = \sqrt(3)$
 

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