Solve for tan(θ) | Homework Equation

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Homework Statement


1 ≤ μ (tan(θ)+1)/(tan(θ)-1)

Homework Equations

The Attempt at a Solution


1 - (tan(θ)-1)/(tan(θ)+1) ≤ μ[/B]
 
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Eagertolearnphysics said:

Homework Statement


1 ≤ μ (tan(θ)+1)/(tan(θ)-1)

Homework Equations

The Attempt at a Solution


PF Rules require you to show your work and your own efforts to solve the problem.
 
Ray Vickson said:
PF Rules require you to show your work and your own efforts to solve the problem.
It's the last step I could get in a bigger problem and I really tried.
 
Eagertolearnphysics said:
1 - (tan(θ)-1)/(tan(θ)+1) ≤ μ
That's wrong. Try that again, but take it in easy steps. A step consists of performing a single operation on one side, and the same operation on the other side. Be clear at each step what operation you are performing on each side.
Since this is an inequality, you have to be careful the inequality is still true after each step. This is because if you multiply or divide both sides by something, and that thing turns out to be negative, the inequality will reverse.
 
Consider three options
tan(θ) <1
tan(θ) >1
tan(θ) = 1

And what is μ? Is it positive? Can it be negative or 0?
 
Irene Kaminkowa said:
Consider three options
tan(θ) <1
tan(θ) >1
tan(θ) = 1

And what is μ? Is it positive? Can it be negative or 0?

There are really four cases. If ##T \equiv \tan(\theta)##, then we can have
[tex]\begin{array}{c}<br /> T < -1\\<br /> -1 \leq T < 1 \\<br /> T = 1\\<br /> T > 1 <br /> \end{array}[/tex]
Knowing the sign of ##\mu## will eliminate one or more of these cases.