prove the identity : cos3x

prove the identity :cos3x =4 cos^3x-3cosx
1. 1 answer
2. asked by Anonymous
3. 1,153 views
Prove the identity cos3x ≡ 4cos^3x - 3cosxThank you so much for the help!
1. 1 answer
2. asked by Autumn
3. 502 views
Prove the identity(Sin²xcosx + cos³x) ÷ sinx = cotx
1. 1 answer
2. 81 views
Prove the identity: cos^4(x)-sin^4(x)=1-2sin^2(x).with explanationim confused on this one cause of the 4th power of the sine.
1. 1 answer
2. asked by Anonymous
3. 660 views
prove that cos3x+sin3x/cos x-sin x=1+2sin2x
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2. asked by sunny
3. 676 views
Verify Identity:cos5x-cos3x=-8sin^2x(2cos^3x-cosx)
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2. asked by Erik
3. 563 views
By expressing 3x as (2x + x) prove thatcos3x = 4cos^3x - 3cosx
1. 1 answer
2. asked by Rin
3. 1,019 views
By expressing 3x as (2x + x) prove thatcos3x = 4cos^3x - 3cosx
1. 1 answer
2. asked by Rin
3. 776 views
Prove: sin3x-sinx/cos3x-cosx=-cot2
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2. asked by Dini
3. 789 views
Having trouble with this problem:Rewrite the expression as an equivalent expression that does not contain powers greater than 1.
1. 2 answers
2. asked by Brian
3. 1,446 views