If sin x = , then find sec x in simplest form.
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Correct answer: C
Explanation
The correct answer is option 3 i.e. .
sin x = 1/√10
⇒ sin2x = 1/10
Formula: sin2x + cos2x = 1
⇒ cos2x = 1 – sin2x = 1 – (1/10) = 9/10
⇒ cos x = √(9/10) = 3/√10
⇒ sec x = 1/cos x = √10/3