Which of the following expression is equivalent to sin(5x) ?
a. sin(3x) cos(2x) + cos(4x) sin(x)
b. sin(4x) cos(x) - cos(4x) sin(x)
c. sin(3x) sin(2x) + cos(3x) cos(2x)
d. sin(3x) sin(2x) - cos(3x) cos(2x)
e. cos(3x) sin(2x) + sin(3x) cos(2x)

Answer :

[tex]Use:\\sin(x+y)=sinxcosy+sinycosx\\-------------------------\\sin5x=sin(3x+2x)=sin3xcos2x+sin2xcos3x\\\\Answer:e)[/tex]
sin(5x)
=sin(3x+2x)
=sin3xcos2x+cos2xsin3x

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