Question

Question #6179b

Answer 1

Given

`cosA/a=cosB/b=cosC/c`

And we know

`a/sinA=b/sinB=c/sinC`

So we have

`cosA/sinA=cosB/sinB=cosC/sinC`

`=>cotA=cotB=cotC`

`=>A=B=C->"triangle is equilateral"`