If $$2 \sin \theta + 15 \cos^2 \theta = 7, 0^\circ < \theta < 90^\circ$$, then $$\tan \theta + \cos \theta + \sec \theta =$$
$$2 \sin \theta + 15 \cos^2 \theta = 7$$
$$2 \sin \theta + 15 (1 - sin^2 \theta) = 7$$
$$2 \sin \theta + 15 - 15 sin^2 \theta = 7$$
$$2 \sin \theta + 8 - 15 sin^2 \theta = 0$$
$$15 sin^2 \theta -Â 2 \sin \theta - 8 = 0 $$
$$sin^2 \theta - \frac{2\sin \theta}{15}Â - \frac{8}{15} = 0 $$
$$sin^2 \theta + \frac{2\sin \theta}{3}Â -Â \frac{4\sin \theta}{5}Â - \frac{8}{15} = 0 $$
$$sin \theta(sin \theta +Â \frac{2}{3})Â -Â \frac{4}{5}(sin \theta + \frac{2}{3})Â = 0 $$
$$(sin \theta -Â \frac{4}{5})(sin \theta + \frac{2}{3}) = 0$$
For $$0^\circ < \theta < 90^\circ$$,
$$sin \theta = \frac{4}{5}$$
Perpendicular = 4
Hypotenuses = 5
By triplet 3-4-5,
Base = 3Â
Now,
$$\tan \theta + \cos \theta + \sec \theta$$
=Â $$\frac{4}{3} + \frac{3}{5} +\frac{5}{3}$$
=Â $$\frac{20 + 9 + 25}{15}$$
=Â $$\frac{54}{15}$$ =Â $$\frac{18}{5}$$
=Â $$3\frac{3}{5}$$
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