Solving sec(x) = −5.2 for x between 0 and 2π

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dragon513
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Q. Solve: secx=-5.2
x is greater than or equal to zero and less than or equal to 2π

I got 1.76 and 4.52, but answer key only has 1.76.

Am I not right?
 

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I find the same answers as you do when I do a quick check using my TI-89. Hmmm :confused:
 
dragon513 said:
Q. Solve: secx=-5.2
x is greater than or equal to zero and less than or equal to 2π
I got 1.76 and 4.52, but answer key only has 1.76.
Am I not right?
Yup, that looks good to me. :smile: Your answer is correct!
 
dragon513 said:
Thank you!
Once you had the first solution 1.76, how did you find the 2nd one?
 
Since you have cos(-x) = cos(x), and [itex]\cos x = \cos (x + 2k \pi) \ \ , k \in \mathbb{Z}[/itex]
So the second one is just:
[tex]- 1.76 + 2 \pi = 4.52[/tex]
 
Thanks for answering, but I was asking dragon513.
dragon513, what was your approach for finding the 2nd angle?