Q.If \( \sec\theta = \csc 5\theta \), then the value of \( \theta \) is — (a) 5° (b) 10° (c) 15° (d) 30°
Answer: C
Given: \( \sec\theta = \csc 5\theta \) ⇒ \( \sec\theta = \sec(90^\circ - 5\theta) \) ⇒ \( \theta = 90^\circ - 5\theta \) ⇒ \( \theta + 5\theta = 90^\circ \) ⇒ \( 6\theta = 90^\circ \) ⇒ \( \theta = 15^\circ \)
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