Q. 12

If A + B + C = π, prove that

tan 2A + tan 2B + tan 2C = tan 2A tan 2B tan 2C

Answer :

= tan 2A + tan 2B + tan 2C


Since A + B + C = π


A + B = π – C


2A + 2B = 2π – 2C


Tan (2A+2B) = tan (2π – 2C)


Since tan (2π – C) = -tan C


Tan (2A + 2B) = -tan 2C


Now using formula,




Tan 2A + tan 2B = -tan 2C + tan 2C tan 2B tan 2A


Tan 2A + tan 2B + tan 2C = tan 2A tan 2B tan 2C


= R.H.S


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RELATED QUESTIONS :

If A + B + C = π, prove that


RS Aggarwal - Mathematics

If A + B + C = π, prove that


RS Aggarwal - Mathematics