Solve Trig Question: 14sin^2y-13=0 for y where 0<y<360

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SUMMARY

The discussion focuses on solving the trigonometric equation 14sin²y - 13 = 0 for y in the interval 0 < y < 360 degrees. The user initially factors the equation to find y = 74.5° and y = 285.5°, but realizes they are missing additional solutions. The correct solutions, 105.5° and 254.5°, are derived using the properties of the sine function and its periodicity. The user acknowledges the need for a deeper understanding of the sine function's behavior in different quadrants to capture all solutions.

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Hello,

I am running into an error and I can't quite figure out what I am doing wrong.

The question is "solve [tex]14\sin^{2}y-13=0[/tex] for y where 0<y<360.

So I factor it down to

[tex]14(sin(y)-\frac{\sqrt{182}}{14})(sin(y)+\frac{\sqrt{182}}{14})=0[/tex] (Thanks integral for showing me how to do this) :P

and thus get

[tex]y=74.5\deg or y=285.5\deg[/tex] by using arcsine, but I am missing solutions somehow. I checked my answer with my calc and it's wrong, I am missing 105.5^ and 254.5^... how though? Adding the period length of 360^ does absolutely nothing. It's probably a small detail that I am overlooking, can someone point me in the right direction? Thanks again.
 
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[tex]180 - 74.5 = 105.5[/tex]

[tex]360 - 105.5 = 254.5[/tex]
 

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