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The Value of Tan X Tan ( π 3 − X ) Tan ( π 3 + X ) is

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प्रश्न

The value of \[\tan x \tan \left( \frac{\pi}{3} - x \right) \tan \left( \frac{\pi}{3} + x \right)\] is

 

विकल्प

  •  cot 3x

  • 2cot 3x

  •  tan 3x

  • 3 tan 3x

MCQ
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उत्तर

\[\frac{\pi}{3} = 60° \]
\[\text{ tan } x \tan\left( 60°  - x \right) \tan\left( 60°  + x \right) = \tan x \times \frac{\tan60°  - \text{ tan } x}{1 + \tan60°\text{ tan } x} \times \frac{\tan60°  + \text{ tan } x}{1 - \tan60°\text{ tan } x}\] 
\[ = \tan x \times \frac{\sqrt{3} - \text{ tan } x}{1 + \sqrt{3}\text{ tan } x} \times \frac{\sqrt{3} + \text{ tan } x}{1 - \sqrt{3}\text{ tan } x}\]
\[ = \frac{\text{ tan } x\left( 3 - \tan^2 x \right)}{1 - 3 \tan^2 x}\]
\[ = \frac{3\text{ tan }x - \tan^3 x}{1 - 3 \tan^2 x}\]
\[ = \tan 3x\]

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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 9.5 [पृष्ठ ४५]

APPEARS IN

आर.डी. शर्मा Mathematics [English] Class 11
अध्याय 9 Values of Trigonometric function at multiples and submultiples of an angle
Exercise 9.5 | Q 31 | पृष्ठ ४५

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