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anonymous
 one year ago
Prove: sin θ  sin θ•cos2 θ = sin3 θ. You must show all work.
anonymous
 one year ago
Prove: sin θ  sin θ•cos2 θ = sin3 θ. You must show all work.

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0idk even where to begin

myininaya
 one year ago
Best ResponseYou've already chosen the best response.1Just thought Maybe you can take the right hand side and show the left hand side Try to play with this thought: sin(3x) is sin(2x+x)

myininaya
 one year ago
Best ResponseYou've already chosen the best response.1That should be a hint to use the sum identity for sin

Idealist10
 one year ago
Best ResponseYou've already chosen the best response.0Memorize the identities for cos 2*theta

myininaya
 one year ago
Best ResponseYou've already chosen the best response.1Though I could be wrong but I don't think this is an identity.

myininaya
 one year ago
Best ResponseYou've already chosen the best response.1One way to find out is to find a counterexample

myininaya
 one year ago
Best ResponseYou've already chosen the best response.1try theta=pi/2 does not work

Idealist10
 one year ago
Best ResponseYou've already chosen the best response.0sin(2x)=2*sin(x)*cos(x)

Idealist10
 one year ago
Best ResponseYou've already chosen the best response.0cos(2x)=2cos^2 (x)1

myininaya
 one year ago
Best ResponseYou've already chosen the best response.1Maybe the problem has been written incorrectly.

myininaya
 one year ago
Best ResponseYou've already chosen the best response.1Unless the instructions say to: Prove if true and give a counterexample if false. If so then I have accidentally given you the answer.

Idealist10
 one year ago
Best ResponseYou've already chosen the best response.0cos(2x)=12sin^2 (x) so what's sin(x)*cos(2x)?
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