Inequalities (trig) + Attempted

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The discussion revolves around solving the equation tanx + 3cotx = 4. The initial steps lead to the quadratic equation tan^2x - 4tanx + 3 = 0, yielding solutions tanx = 1 and tanx = 3. For tanx = 1, the solution is correctly identified as π/4 + nπ, where n is an integer. However, tan^-1(3) cannot be expressed in terms of π, and it must be left as is. The overall approach and calculations are confirmed to be correct.
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Homework Statement



tanx + 3cotx = 4

Homework Equations





The Attempt at a Solution



Heres my attempt:

tanx + 3/tanx - 4 = 0
(tan^2x -4tanx + 3) / tanx = 0

tan^2x - 4 tanx + 3

(tanx - 3 ) (tanx - 1 ) = 0

tan = 3, tan = 1

im not sure about tan = 3, but for tan = 1 , pi/4 +180n,
is this correct? if it is how would i go about findin solutions for tan=3.

please help,
thanks.
 
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The same way you solved tanx=1

tanx=3, the principle angle is tan-1(3)
 
how would we represent tan^-1(3) interms of radians ?
calculators are not allowed in our school, is there a way ?
 
lovemake1 said:
how would we represent tan^-1(3) interms of radians ?
calculators are not allowed in our school, is there a way ?

Unfortunately there is not.
 
hmm..
so we just find solutions for tan = 1 ?
 
lovemake1 said:
im not sure about tan = 3, but for tan = 1 , pi/4 +180n,
is this correct? if it is how would i go about findin solutions for tan=3.
"pi/4 +180n" -> Don't mix degree and radian measure. Also, state what "n" is. You should write
\frac{\pi}{4} + n \pi, n \in \mathbb{Z}

lovemake1 said:
hmm..
so we just find solutions for tan = 1 ?
No, you still need both solutions. The other could be written as
\tan^{-1} 3 + n \pi, n \in \mathbb{Z}
 
tan^-1(3) + npi
how do you write that interms of pi?

i've never seen anything like that. could you please give me an example?
 
lovemake1 said:
tan^-1(3) + npi
how do you write that interms of pi?

i've never seen anything like that. could you please give me an example?

you can't write tan-1(3) in terms of pi. That is why you have to leave it as is.
 
ok, just to make sure.. are my previous steps correct?
just to double check. thanks
 
  • #10
lovemake1 said:
ok, just to make sure.. are my previous steps correct?
just to double check. thanks

Yes they are correct.
 

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