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If sin x + cosec x = 2, then what is \(sin^{9}x + cosec^{9}x\) equal to ?

A) 2
B) 18
C) 512
D) 1024

Correct Answer:

A) 2

Description for Correct answer:
sinx + cosecx = 2

\( \Large x = \frac{\pi}{2}\)

\( \Large sin^{9}x + cosec^{9}x = \left(sin\frac{ \pi }{2}\right)^{9} + \left(cosec\frac{ \pi }{2}\right)^{9} \)

= 1 + 1 = 2

Option (a) is correct

Part of solved CDS Maths(1) questions and answers : Exams >> CDSE >> CDS Maths(1)

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