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If in ∆Abc, Tan a + Tan B + Tan C = 6, Then Cot a Cot B Cot C =

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प्रश्न

If in ∆ABC, tan A + tan B + tan C = 6, then cot A cot B cot C =

पर्याय

  • 6

  • 1

  • \[\frac{1}{6}\]

     

  • None of these

MCQ
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उत्तर

\[\frac{1}{6}\]
In triangle ABC,
\[ A + B + C = \pi\]
\[\text{ We know that }\tan\left( A + B + C \right) = \frac{\tan A + \tan B + \tan C - \tan A \tan B \tan C}{1 - \tan A \tan B - \tan B \tan C - \tan C \tan A}\]
\[\text{ and }\tan \pi = 0 . \]
\[ \therefore \tan A + \tan B + \tan C - \tan A \tan B \tan C = 0\]
\[\tan A + \tan B + \tan C = \tan A \tan B \tan C\]
If tan A+tan B+tan C =6,
tan A tan B tan C =6
\[\Rightarrow \frac{1}{\tan A \tan B \tan C} = \frac{1}{6}\]
\[ \Rightarrow \cot A \cot B \cot C = \frac{1}{6}\]
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पाठ 7: Values of Trigonometric function at sum or difference of angles - Exercise 7.4 [पृष्ठ २७]

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आर.डी. शर्मा Mathematics [English] Class 11
पाठ 7 Values of Trigonometric function at sum or difference of angles
Exercise 7.4 | Q 6 | पृष्ठ २७

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