Trigonometry: If 13 sin x = 5 where x is the greatest positive angle, then find ...

Sand

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If 13 sin x = 5 where x is the greatest positive angle, then find the numerical value of sec (180°-x) + cos (270°-x)
 
If 13 sin x = 5 where x is the greatest positive angle, then find the numerical value of sec (180°-x) + cos (270°-x)
What does your book mean by "x is the greatest positive angle"? There will be infinitely-many solutions to the posted equation, because that's how periodic functions work. Are you maybe supposed to use the largest angle that happens to fall within the first period, 0 degrees to 359 degrees?

When you reply, please include a clear listing of your thoughts and efforts so far, so we can see what's going on. Thank you! ;)
 
What does your book mean by "x is the greatest positive angle"? There will be infinitely-many solutions to the posted equation, because that's how periodic functions work. Are you maybe supposed to use the largest angle that happens to fall within the first period, 0 degrees to 359 degrees?

When you reply, please include a clear listing of your thoughts and efforts so far, so we can see what's going on. Thank you! ;)
Unfortunately, this question was on my final algebra and trig exam, and not in the book ?
I lost marks because of it, my answer was a three digit negative fraction ? I tried searching for where this kind of question was mentioned in the book but not a single question was in this format
What I got was this:
Sin x = 5/13.
Sec(180-x)+cos(270-x)= -sec x - sin x
I got the cos x from the rule (x^2+y^2=1)
Cos x= 12/13
So sec x= 13/12
So - 13/12-5/13=-229/156
Which looks like a really really wrong answer ?
 
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