[" If "2cos A+3cos B+5cos C=0],[=2sin A+3sin B+5sin C" then "],[8cos3A+27cos3B+125cos3C=],[k cos(A+B+C)" then "k=]

If 2cos A+3cos B+5cos C=0=2sin A+3sin B+5sin C then 3A+27cos3B+125cos3C=k cos(A+B+C) then k is

a.cos A + b.cos B + c.cos C = 2a sin B sin C

a cos A + b cos B + c cos C = 2a sin B sin C

If sinA + sin B + sin C=3, then: cos A + cos B + cos C=

cos2B + cos2A-cos2C = 1-4sin A sin B cos C

If cos A+coa B+cos C=sin A+sin B+sin C=0 the values of (cos3A+cos3B+cos C)/(cos(A+B+C))

Assertion (A): If A, B, C are the angles of a triangle such that cos A + cos B + Cos C = 0 = sin A + sin B + sin C then cos 3A + cos 3B + cos 3C = -3 Reason (R) : If cos alpha + cos beta + cos gamma = 0 = sin alpha + sin beta + singamma then cos 3 alpha + cos 3 beta + cos 3 gamma = 3 cos (gamma+alpha+beta)

If A+B+C= pi and cos A+cos B+cos C=0=sin A+sin B+sin C , then sin 3A+sin 3B+sin 3C =

If cos A+cos B+cos C=0sin A+sin B+sin C=0 and A+B+C=180^(@), then the value of cos3A+cos3B+cos3C is

If sin A + sin B + sin C = 3, then cos A + cos B + cos C is equal to