"The Expression"=4sinx+5sin6xThe Expression=4sinx+5sin6x,
=4sinx+5(2color(red)(sin3x)color(blue)(cos3x))=4sinx+5(2sin3xcos3x),
=4sinx+10color(red)((3sinx-4sin^3x))color(blue)((4cos^3x-3cosx))=4sinx+10(3sinx−4sin3x)(4cos3x−3cosx),
=4sinx+10{sinx(3-4sin^2x)}{cosx(4cos^2x-3)}=4sinx+10{sinx(3−4sin2x)}{cosx(4cos2x−3)},
=4sinx+10sinxcosx(3-4sin^2x)(4cos^2x-3)=4sinx+10sinxcosx(3−4sin2x)(4cos2x−3),
=4sinx+10sinxcosx(3-4sin^2x){4(1-sin^2x)-3}=4sinx+10sinxcosx(3−4sin2x){4(1−sin2x)−3},
=4sinx+10sinxcosx(3-4sin^2x)(1-4sin^2x)=4sinx+10sinxcosx(3−4sin2x)(1−4sin2x),
=4sinx+10sinxcosx(3-16sin^2x+16sin^4x)=4sinx+10sinxcosx(3−16sin2x+16sin4x).
rArr"The Exp."=2sinx{2+5cosx(3-16sin^2x+16sin^4x)}⇒The Exp.=2sinx{2+5cosx(3−16sin2x+16sin4x)}.