In any triangle ABC, prove that
c - bcos A / b - ccos A = cos B/ cos C
Urgent
c - bcos A / b - ccos A = cos B/ cos C
By the projection formula:
c = bcosA + acosB and b = ccosA + acosC
Therefore, c - bcosA = acosB and b - ccosA = acosC
Therefore, (c - bcosA)/(b - cosA) = cosB/cosC
By the projection formula:
c = bcosA + acosB and b = ccosA + acosC
Therefore, c - bcosA = acosB and b - ccosA = acosC
Therefore, (c - bcosA)/(b - cosA) = cosB/cosC