If $f\left( x \right) = {\cos ^2}\,\,x + {\sec ^2}\,\,x$, its value always is

JEE MATHEMATICS MCQ: TRIGONOMETRY RATIOS

1 Easy

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Application +4 | -1

f\left( x \right) = {\cos ^2}\,\,x + {\sec ^2}\,\,x

, its value always is

View answer and explanation

Correct option: B

f\left( x \right) = 1

Option D (

f(x) \ge 2

) is correct because the minimum value of

{\cos ^2}x + {\sec ^2}x

occurs when

\cos^2 x = 1

and

\sec^2 x = 1

, so the minimum value is 2.

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