2. Questions Bank
  3. JEE Main & Advanced
  4. Mathematics
  5. Trigonometric Equations

JEE Main & Advanced Mathematics Trigonometric Equations Question Bank Relation between sides and angles, Solutions of triangles

  • question_answer
    In triangle \[ABC\], \[(b+c)\cos A+(c+a)\cos B\] \[+(a+b)\cos C=\] [MP PET 1985]

    A) 0

    B) 1

    C) \[a+b+c\]

    D) \[2(a+b+c)\]

    Correct Answer: C

    Solution :

    \[(b+c)\cos A+(c+a)\cos B+(a+b)\cos C=a+b+c\] From expanding and collecting terms using projection rule, \[a=b\cos C+c\cos B\]etc.


You need to login to perform this action.
You will be redirected in 3 sec spinner