1.

If ` cos x + 2 cos y + 3 cos z = sin x + 2 sin y + 3 sin z = 0` then the value of ` sin 3x + 8 sin 3y + 27 sin 3z` is :

Answer» `cosx+2cosy+3cosz=0`
`isinnx+2isiny+3isinz=0`
`e^(ix)+2e^(iy)+3e^(iz)=0`
`a^3+b^3+c^3=3abc`
`e^(13x)+2e^(i3y)+27e^(13z)=18e^(i(x+y+z))`
`cos3x+isinx+8cos3y+i8sinn3y+27cos3z+isin3z=18[cos(x+y+z)+(isin(x+y+z)]`
`sin3x+8sin3y+27sin3z=18sin(x+y+z)`.


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