Trig Identities Question NEED HELP

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Homework Help Overview

The discussion revolves around proving a trigonometric identity involving sine and cosine functions. The original poster presents an equation that appears to be ambiguous in its current format.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • Participants are questioning the clarity of the original equation and suggest the need for proper parentheses. There is mention of double angle identities, with some participants expressing uncertainty about how to apply them effectively.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the problem. Some guidance has been offered regarding the use of double angle identities, and one participant hints at a potential simplification involving a perfect square.

Contextual Notes

There is a noted ambiguity in the original equation, which may affect the understanding of what needs to be proven. Participants are also reflecting on their familiarity with trigonometric identities and their application.

darrenc
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How do I prove that

(1+sin2x) = (cosx)
(cosx + sinx) (cosx - sinx)
 
Last edited:
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I can't tell what you need to prove, since what you have written is ambiguous. Put parentheses around the terms in each numerator and in each denominator.

Do you know any double angle identities?
 
Mark44 said:
I can't tell what you need to prove, since what you have written is ambiguous. Put parentheses around the terms in each numerator and in each denominator.

Do you know any double angle identities?

I know double angle identities such as

sin2x = 2sinxcosx and the three cos2x ones but i can't get anything to work

I've got all the formulas but i don't know how to use them to make it work
 
Dude, i got pissed off at this same question yesterday. The key is 1 +2sinxcosx is a perfect square!
 

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