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In a triangle A B C , if acosA=bcosB , s...

In a triangle `A B C ,` if `acosA=bcosB ,` show that the triangle is either isosceles or right angled.

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From sine law, we have,
`a/sinA = b/sinB = c/sinC = k`
`=> a = ksinA, b = ksin B, c = ksinC`
Now, it is given that ,
`acosA = bcosB`
`=>ksinAcosA = ksinBcosB`
`=>sinAcosA = sinBcosB`
`=>2sinAcosA = 2sinBcosB`
...
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