Mastering Trig: Simplify Equations with Easy Tricks | Learn the Basics

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Homework Help Overview

The discussion revolves around simplifying trigonometric equations, specifically involving the function r = sin(3x) and its derivative. Participants are exploring the manipulation of trigonometric identities and expressions.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants are attempting to simplify expressions involving trigonometric functions and are questioning the validity of combining different trigonometric functions. There is discussion about using identities to rewrite expressions.

Discussion Status

Some guidance has been offered regarding the use of trigonometric identities to simplify the expressions. Participants are actively engaging with each other's suggestions and clarifying misunderstandings, though there is no explicit consensus on the final form of the expression.

Contextual Notes

There appears to be some uncertainty regarding the application of trigonometric identities and when functions can be combined, indicating a need for further exploration of these concepts.

lemurs
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ok.. title says it all I feeling really stupid right now and seem to be having trouble with elementary stuff here..
given r= sin 3x

dr= cos 3x * 3
dx

i got that . but next step in the equation i am doing is

3cos 3x * cos x

as i said feeling stupid si it

3 cos^2 3x?
 
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No.

You can only combine trig functions like that when the arguments are equal.
 
It's certainly not. If you're in doubt, write it as 3(cos(3x))^2.

To rewrite cos 3x * cos x, employ the identities involving cos(A+B) and cos(A-B).
 
ok i understna what you wrote neutrino
so i but i got that 3 out front so with the little identity bit wuld it be

3(1/2(cos(a-b)+cos(a+b)))
 
Yes, if it makes the problem any simpler.
 

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