मराठी

If π < X < 3 π 2 , Then Write the Value of √ 1 − Cos 2 X 1 + Cos 2 X .

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प्रश्न

If \[\pi < x < \frac{3\pi}{2}\], then write the value of \[\sqrt{\frac{1 - \cos 2x}{1 + \cos 2x}}\] . 

 
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उत्तर

\[\text{ We have } , \]
\[\sqrt{\frac{1 - \cos2x}{1 + \cos2x}} = \sqrt{\frac{2 \sin^2 x}{2 \cos^2 x}}\]
\[ = \frac{\left| \text{ sin } x \right|}{\left| \text{ cos } x \right|}\]
\[ = \frac{\left| \text{ sin } x \right|}{\left| \text{ cos } x \right|} \]
\[ = \frac{- \text{ sin } x}{- \text{ cos } x} \left( \because \pi < x < \frac{3\pi}{2} \right) \]
\[ \therefore \sqrt{\frac{1 - \cos2x}{1 + \cos2x}} = \text{ tan } x\]

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Values of Trigonometric Functions at Multiples and Submultiples of an Angle
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पाठ 9: Values of Trigonometric function at multiples and submultiples of an angle - Exercise 9.4 [पृष्ठ ४२]

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आर.डी. शर्मा Mathematics [English] Class 11
पाठ 9 Values of Trigonometric function at multiples and submultiples of an angle
Exercise 9.4 | Q 6 | पृष्ठ ४२

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