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P Answer the Following Questions in One Word Or One Sentence Or as per Exact Requirement of the Question. If in a ∆Abc, Cos a A = Cos B B = Cos C C - Mathematics

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प्रश्न

Answer the following questions in one word or one sentence or as per exact requirement of the question.  

If in a ∆ABC, cosAa=cosBb=cosCc then find the measures of angles ABC

उत्तर

In ∆ABC, 

cosAa=cosBb=cosCc
cosAksinA=cosBksinB=cosCksinC( Using sine rule )
cotA=cotB=cotC
A=B=C
⇒ ∆ABC is an equilateral triangle.
∴ A = B = C = 60º 

 

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Sine and Cosine Formulae and Their Applications
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 10: Sine and cosine formulae and their applications - Exercise 10.3 [पृष्ठ २६]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 11
अध्याय 10 Sine and cosine formulae and their applications
Exercise 10.3 | Q 8 | पृष्ठ २६

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