SOLUTION: verify Sin(4x)=4sin(x)cos^3(x)-4sin^3(x)cos(x)?

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Question 514140: verify Sin(4x)=4sin(x)cos^3(x)-4sin^3(x)cos(x)?
Answer by lwsshak3(11628) About Me  (Show Source):
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verify Sin(4x)=4sin(x)cos^3(x)-4sin^3(x)cos(x)?
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Sin(4x)=4sin(x)cos^3(x)-4sin^3(x)cos(x)
starting with left side
sin(4x)=2sin(2x)Cos(2x)
=2[2sin(x)cos(x)(cos^2(x)-sin^2(x)]
=2[2sin(x)cos^3(x)-2sin^3(x)cos(x)]
=4sin(x)cos^3(x)-4sin^3(x)cos(x)
verified:
left side = right side