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If π 4 < X < π 2 , Then Write the Value of √ 1 − Sin 2 X .

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प्रश्न

If \[\frac{\pi}{4} < x < \frac{\pi}{2}\], then write the value of \[\sqrt{1 - \sin 2x}\] .

 

 

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उत्तर

\[\text{ We have } , \]
\[\sqrt{1 - \sin2x}\]
\[ = \sqrt{\sin^2 x + \cos^2 x - 2\text{ sin } x \text{ cos } x}\]
\[ = \sqrt{\left( \text{ sin } x - \text{ cos } x \right)^2} \]
\[ = \left| \text{ sin } x - \text{ cos } x \right|\]
\[ = \text{ sin } x - \text{ cos } x\]
\[ \left[ \because \text{ sin } x > \text{ cos } x \text{ for }  \frac{\pi}{4} < x < \frac{\pi}{2} \right]\]
\[ \therefore \sqrt{1 - \text{ sin } 2x} = \text{ sin } x - \text{ cos } x\]

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Values of Trigonometric Functions at Multiples and Submultiples of an Angle
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 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
अध्याय 9 Values of Trigonometric function at multiples and submultiples of an angle
Exercise 9.4 | Q 9 | पृष्ठ ४२

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