मराठी

The number of real solutions of the equation 1+cos2x=2cos-1(cosx) in [π2,π] is ______.

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प्रश्न

The number of real solutions of the equation `sqrt(1 + cos 2x) = sqrt(2) cos^-1 (cos x)` in `[pi/2, pi]` is ______.

पर्याय

  • 0

  • 1

  • 2

  • Infinite

MCQ
रिकाम्या जागा भरा
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उत्तर

The number of real solutions of the equation `sqrt(1 + cos 2x) = sqrt(2) cos^-1 (cos x)` in `[pi/2, pi]` is 0.

Explanation:

We have `sqrt(1 + cos 2x) = sqrt(2) cos^-1 (cos x)` 

⇒ `sqrt(2 cos^2x) = sqrt(2)x`        ...`[because cos^-1 (cos x) = x]`

⇒ `sqrt(2) cos x = sqrt(2)x`

⇒ cos x = x

∴ There are no solution for given equation.

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पाठ 2: Inverse Trigonometric Functions - Exercise [पृष्ठ ३९]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 12
पाठ 2 Inverse Trigonometric Functions
Exercise | Q 36 | पृष्ठ ३९

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