How do I simplify this inequality

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SUMMARY

The discussion focuses on simplifying the inequality Mg * abs(sin(θ) - cos(θ)) <= μMg * (cos(θ) + sin(θ)) to derive the condition tan(θ) <= (1+μ) / (1-μ) under the assumption that tan(θ) >= 1. The key step involves dividing the inequality by cos(θ) to isolate tan(θ). This approach effectively transforms the original inequality into a more manageable form, allowing for straightforward manipulation and simplification.

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MeMoses
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Homework Statement


So I'm following along with my physics book and I get to the point where
Mg * abs(sin(θ) - cos(θ)) <= μMg * (cos(θ) + sin(θ)
Next they say: If tan(θ) >= 1 then
sin(θ) - cos(θ) <= μ(cos(θ) + sin(θ)) => tan(θ) <= (1+μ) / (1-μ)


Homework Equations





The Attempt at a Solution


How do I go from sin(θ) - cos(θ) <= μ(cos(θ) + sin(θ)) to tan(θ) <= (1+μ) / (1-μ)?
Could someone walk me through this or at least get me started? Thanks
 
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MeMoses said:

Homework Statement


So I'm following along with my physics book and I get to the point where
Mg * abs(sin(θ) - cos(θ)) <= μMg * (cos(θ) + sin(θ)
Next they say: If tan(θ) >= 1 then
sin(θ) - cos(θ) <= μ(cos(θ) + sin(θ)) => tan(θ) <= (1+μ) / (1-μ)

Homework Equations



The Attempt at a Solution


How do I go from sin(θ) - cos(θ) <= μ(cos(θ) + sin(θ)) to tan(θ) <= (1+μ) / (1-μ)?
Could someone walk me through this or at least get me started? Thanks
You get to do most of the walking. (Hopefully, you know by now that that's how we do things here at PF.)

Take
[itex]\sin(\theta) - \cos(\theta) \le \mu(\cos(\theta) + \sin(\theta))[/itex]​
and divide both sides by cos(θ) .

Simplify, and the only trig function remaining is tan .

Now, try to isolate tan(θ).
 
Thanks, that's all I needed
 

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