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JEE MATHEMATICS MCQ: TRIGONOMETRIC EQUATIONS

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Application +4 | -1

If

0 \leq x \leq \pi

and

81^{\sin ^{2} x}+81^{\cos ^{2} x}=30

, then

x=

View answer and explanation

Correct option: A

\pi / 6

Option A (

\pi / 6

) is correct because substituting

x = \pi/6

into the equation

81^{\sin^2 x} + 81^{\cos^2 x} = 30

satisfies the equation.

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x \in\left[0, \frac{\pi}{4}\right]

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