cos a + cos b + cos c = sin a +sin b+ sin c =0 then value of cos 3a + cos 3b+ cos 3c is....

a)0

b)cos(a+b+c)

c)3 cos(a+b+c)

d)3 sin(a+b+c)

Please show steps.

Meghendra Agrawal

7 Years agoGrade