Simplify Trigonometry expression

AI Thread Summary
The discussion focuses on simplifying the expression to tan(theta) by understanding its relationship with sin(theta) and cos(theta). Participants clarify that tan(theta) is defined as sin(theta) divided by cos(theta). The concept of the componendo-dividendo property of equal ratios is introduced as a method to manipulate the expression. An example is provided, demonstrating how to transform an inequality involving sin(theta) and cos(theta) into one involving tan(theta). The conversation concludes with appreciation for the insights shared, highlighting the collaborative nature of problem-solving in trigonometry.
Eagertolearnphysics
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Homework Statement


I want to know how he simplified this expression to tan (theta)
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Homework Equations

The Attempt at a Solution

 
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Hint: How is ##\tan \theta## related to ##\sin \theta## and ##\cos \theta##?
 
Fightfish said:
Hint: How is ##\tan \theta## related to ##\sin \theta## and ##\cos \theta##?
I know it's Sin/Cos however, I don't know how he did it.
 
Eagertolearnphysics said:
I know it's Sin/Cos however, I don't know how he did it.
So how do you get ##\sin \theta / \cos \theta## from the original expressions?
 
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Eagertolearnphysics said:
I know it's Sin/Cos however, I don't know how he did it.
Are you familiar with the componendo-dividendo property of equal ratios?
If a/b=c/d, then (a+b)/(a-b)=(c+d)/(c-d).
 
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I really would like to thank you guys I got it. I was hesitating to post the question as I thought it was too obvious. Thanks again :smile:
 
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In case somebody else reading this didn't get the answer, we can take an expression like this:

##\sin \theta - \cos \theta \le \mu (\cos \theta + \sin \theta)##

and divide both sides by ##\cos \theta## to get

## \tan \theta - 1 \le \mu (1 + \tan \theta)##

then go from there.
 
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