What will be the solution of the mentioned problem??

#If,A+B+C=piandcotA+cotB+cotC=sqrt3,#
then show that,#color(blue)(A=B=C).#

1 Answer
Jan 12, 2018

We can show it in the following way.
Given #A+B+C=pi#

  1. First assumption: We are discussing three angles #A,B and C# of a triangle.
  2. If #A=B=C=>DeltaABC# is an equilateral triangle.
  3. All angles of an equilateral triangle are equal and each #=60^@#

Now

#cotA+cotB+cotC=cot60^@+cot60^@+cot60^@#
#=3cot60^@=3xx1/sqrt3=sqrt3#
Which is #=#RHS of the given equation.

Hence our assumption and its following results are true.
Hence proved.