Simplify Trigonometry expression

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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.