If $$12 \cos^2 \theta - 2 \sin^2 \theta + 3\cos \theta = 3, 0^\circ < \theta < 90^\circ$$, then what is the value of $$\frac{\cosec \theta + \sec \theta}{\tan \theta + \cot \theta}$$?
$$12 \cos^2 \theta - 2 \sin^2 \theta + 3\cos \theta = 3$$
$$12 \cos^2 \theta - 2(1 -Â \cos^2 \theta) + 3\cos \theta = 3$$
$$14 \cos^2 \theta + 3\cos \theta = 5$$
Put the value of $$\theta = 60\degree$$,
$$14 \cos^2 60\degree + 3\cos 60\degree = 5$$
$$14 \times \frac{1}{2} + 3Â \times \frac{1}{2} = 5$$
5 = 5
L.H.S. = R.H.S.
$$\frac{\cosec \theta + \sec \theta}{\tan \theta + \cot \theta}$$
=Â $$\frac{\cosec 60\degree + \sec 60\degree}{\tan 60\degree + \cot 60\degree}$$
= $$\frac{\frac{2}{\sqrt3} + 2}{\sqrt3 + \frac{1}{\sqrt3}}$$
= $$\frac{\frac{2 + 2\sqrt3}{\sqrt3}}{\frac{3 +Â 1}{\sqrt3}}$$
= $$\frac{1 + \sqrt3}{2}$$
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