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According to the summary for acute angles, which statement is always true?
A$\sin A$ is always greater than 1
B$\cos A$ can exceed 1
C$\sec A$ is always greater than or equal to 1 for $0^\circ\leq A<90^\circ$
D$\cosec A$ is always less than 1
Answer & Solution
Correct answer: C. $\sec A$ is always greater than or equal to 1 for $0^\circ\leq A<90^\circ$
The summary states that the value of $\sin A$ or $\cos A$ never exceeds 1. It also states that $\sec A$ for $0^\circ\leq A<90^\circ$ and $\cosec A$ for $0^\circ<A\leq90^\circ$ are always greater than or equal to 1. Hence option C is correct.
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