Solution to this trigonometric equation

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Homework Help Overview

The discussion revolves around solving a trigonometric equation involving the tangent function, specifically in the context of finding the value of x in the equation tan(x) = ((1 + tan(1))(1 + tan(2)) - 2) / ((1 - tan(1))(1 - tan(2)) - 2). Participants explore various algebraic manipulations and trigonometric identities to simplify the expression.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants attempt to simplify the original equation by multiplying through parentheses and questioning the presence of trigonometric identities. There are inquiries about whether the angles are in radians or degrees, and suggestions to divide the numerator and denominator by specific terms to facilitate simplification.

Discussion Status

Several participants have provided guidance on how to manipulate the equation further, with some suggesting specific forms to aim for. There is an ongoing exploration of potential simplifications and substitutions related to trigonometric identities, but no consensus has been reached on a final method or solution.

Contextual Notes

Participants note the ambiguity regarding whether the angles are in radians or degrees, which may affect the interpretation of the problem. Additionally, there are indications of imposed homework constraints that guide the discussion towards algebraic manipulation rather than direct solutions.

diredragon
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Homework Statement


##tanx=\frac{(1+tan1)(1+tan2)-2}{(1-tan1)(1-tan2)-2}## find x

Homework Equations


3. The Attempt at a Solution [/B]
I tried multiplying through the paranthesis and arrived at ##tanx=\frac{(tan1tan2-1)+(tan2+tan1)}{(tan1tan2-1)-(tan2+tan1)}## and i don't know if this is any simpler than what was originally set. Is there a trigonometric identity at play here?
 
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diredragon said:

Homework Statement


##tanx=\frac{(1+tan1)(1+tan2)-2}{(1-tan1)(1-tan2)-2}## find x

Homework Equations


3. The Attempt at a Solution [/B]
I tried multiplying through the parentheses and arrived at ##tanx=\frac{(tan1tan2-1)+(tan2+tan1)}{(tan1tan2-1)-(tan2+tan1)}## and i don't know if this is any simpler than what was originally set. Is there a trigonometric identity at play here?
Is that really tan(1) and tan(2), as in 1 and 2 radians?
 
Whatever it is, divide the numerator & denominator by ##\ tan1\,tan2 -1 \ ##.
 
SammyS said:
Whatever it is, divide the numerator & denominator by ##\ tan1\,tan2 -1 \ ##.
It's in degrees. So i divided both num and den by ##tan1tan2 - 1## and i get
##tanx=\frac{(tan1)^2(tan2)^2-2tan1tan2+1+(tan2)^2tan1-tan2+(tan1)^2tan2-tan1}{(tan1)^(tan2)^2-2tan1tan2+1-(tan2)^2tan1+tan2-(tan1)^2-tan1}##
What should i do now?
 
From post #1 and using SammyS's suggestion you should get it into the form: (1 + A)/(1 - A)

Can you try it again.
 
Oh, well then it is
##tanx=\frac{1+\frac{tan1+tan2}{tan1tan2-1}}{1-\frac{tan1+tan2}{tan1tan2-1}}##
Is there a way to simplify this?
 
Ask google to search on tan(a+b) (or some trig expression like that) and see whether you can substitute something for that expression you have for the term I designated by A.
 
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NascentOxygen said:
Ask google to search on tan(a+b) (or some trig expression like that) and see whether you can substitute something for that expression you have for the term I designated by A.
##tanx=\frac{1-tan3}{1+tan3}## but that's as far as the simolification goes right? Now the use of calculator is required. It says that the answer is ##x=42## in degrees.
 
Yeah i solved it. I used ##tan45-tan3## and the identity to arrive at ##tanx=tan42##
 
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