Find theta: Solving csc & ctn Equations with x-6 & x+5

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Homework Help Overview

The discussion revolves around solving equations involving the cosecant and cotangent functions, specifically csc(theta) and ctn(theta), expressed in terms of a variable x. The goal is to find the angle theta based on the given equations.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants suggest expressing sin(theta) and tan(theta) in terms of x and using trigonometric identities to simplify the problem. There are also recommendations to draw a triangle to visualize the relationships between the sides and angles.

Discussion Status

Some participants have provided guiding questions and suggestions for approaching the problem, such as using trigonometric identities and the Pythagorean theorem. Multiple methods are being explored, including algebraic manipulation and geometric interpretation.

Contextual Notes

There is an emphasis on showing work and understanding the definitions of the trigonometric functions involved. Participants are encouraged to clarify their assumptions and the relationships between the functions.

lucifer_x
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if

csc theta=
x-6
x-2

and

ctn theta=
x+5
x-2

find theta
 
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You need to show us some work.

Here are some questions to get you moving.

What is sin [itex]\theta[/itex] ?

What is Tan [itex]\theta[/itex] ?

Now use what you know about the definition of sin and Tan to draw a triangle. Apply Pythagorean theorem.
 
First you need to solve for x. That means making use of a trigo identity to get theta out of the way. Express sin theta and cos theta in terms of x, then apply that trigo identity.
 
Trig identities are one way to shift from one function to another (for example, if you know sec(x)= a/b and want to find tan(x), write a trig identity that converts sec to tan, say tan2(x)= sec2(x)- 1 and so that tan2(x)= x2- 1 and tan(x)= \sqrt{a^2/b^2- 1}= .\sqrt{a^2- b^2}/b [/itex].

Still another, perhaps simpler, method is to draw a triangle with one angle x and write in appropriate lengths for the sides. In the above example, if sec(x)= a/b then, since sec= 1/cos or "hypotenuse over near side", our triangle would have hypotenuse a and near side b. By the Pythagorean theorem, the "opposite side" has length [itex]\sqrt{a^2- b^2}[/itex] and so tan(x), "opposite side over near side", is [itex]\sqrt{a^2- b^2}/b[/itex]

But don't use the word "reciprocals" here. Reciprocals are specifically the "multiplicative inverses". Here you are concerned with "functional inverses".
 

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