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Briggs
Oct9-05, 02:23 PM
I have been set an exercise from my text book to do for homework but I am having some problems on one of the questions, I havn't encountered any of this type before and I am quite stumped.

"Eliminate \theta from equations x=2+\csc\theta and y=\frac{1}{4}\tan\theta"

So I am guessing I start off with x=y but then... :confused:

Fermat
Oct9-05, 03:56 PM
start off by getting separate expressions for cscθ and tanθ from each of your two eqns.
Now you have to eliminate θ.
Can you do it from there ?

Briggs
Oct9-05, 04:02 PM
So for the first one would it goto,
2+\frac{1}{\sin\theta}=3+\cot\theta Then try eliminate theta from there?

Fermat
Oct9-05, 04:31 PM
not quite.
get two separate expressions. One for cscθ and one for tanθ.
Then find a trig identity involving the trig functions. You will have to manipulate the functions to get the identity.

Briggs
Oct9-05, 05:42 PM
I'm not sure what you are saying, get an expression for each equation so for the first one would become 2+\cot\theta and the second one \frac{1}{4}\csc\theta-\frac{1}{4} then put them equal to each other and try solve it?
I would appreciate it if you could show me the first step in tex form

Fermat
Oct9-05, 05:47 PM
hang on a minute.

Fermat
Oct9-05, 05:51 PM
x = 2 + cscθ
y = ¼tanθ

cscθ = x - 2
tanθ = 4y

1 + tan²θ = sec²θ

Briggs
Oct9-05, 05:57 PM
Ahhh, it all becomes clear. Thanks a lot for the help It seems so easy now.