math help: I need help solving these trig identities, PLEASE! - Help.com

I need help solving these trig identities, PLEASE!

!!

1. 2sinxsin3x=(1-cos2x)(1+cos2x)
2. sin2x-sinx/cos2x+cosx=1-cosx/sinx
3. 2cos4xsin2x=2sin3xcos3x-2sinxcosx
4. cos(x+y)cos(x-y)=cos^2x+cos^2y-1
5. cos(x+y)sin(x-y)=sinxcosx-sinycosy

This open post was written 5 months, 2 weeks ago | V/U/S: 126, 0, 1 | Edit Post | Leave a reply | Report Post


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Since writing this post Arramos2 may have helped people, but has not within the last 4 days. Arramos2 is a verified member, has been around for 5 months, 2 weeks and has 1 posts and 0 replies to their name.

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trigonometry, math, Identities, engineer (How Tags Affect Reciprocity)

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