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Trigonometry solving

Can someone please answer and explain this? ty
Solve between -180 θ 180
cos θ = 0.6
sin θ = 0.8
tan θ = - 0.62
cos θ = - 0.342
(edited 6 years ago)
Original post by kurro
Can someone please answer and explain this? ty
Solve between -18 θ 180
cos θ = 0.6
sin θ = 0.8
tan θ = - 0.62
cos θ = - 0.342


Look in your textbook for explanation then have a go at these yourself first?
Original post by RDKGames
Look in your textbook for explanation then have a go at these yourself first?

I dont understand the '-18 θ 18' part normaly it is 360 or 720. Plus i dont have text book :frown:
Original post by RDKGames
Look in your textbook for explanation then have a go at these yourself first?

For the first one i got theta=53.1 and 306.9 is that correct?
Original post by kurro
I dont understand the '-18 θ 18' part normaly it is 360 or 720. Plus i dont have text book :frown:


It should be 180<θ<180-180 < \theta < 180, not 18's. Just solve those eqs. in this range using the method you were taught to use?
Original post by kurro
For the first one i got theta=53.1 and 306.9 is that correct?


Looks good.
Original post by RDKGames
Looks good.

306.9 is not in the range -180 θ 180so im not sure about that one?
Original post by kurro
For the first one i got theta=53.1 and 306.9 is that correct?


53.1 is good but 306.9 is outside the range. Workout all the possible values between -180 and 180
Original post by kurro
306.9 is not in the range -180 θ 180so im not sure about that one?


Yeah sorry, got distracted, you need to disregard that one. Cosine repeats itself every 360 degrees to just keep adding or subtracting 360 to both of those answers and see if you get anything else in the range.
Original post by AnnaBanana2000
53.1 is good but 306.9 is outside the range. Workout all the possible values between -180 and 180


ty
Original post by RDKGames
Yeah sorry, got distracted, you need to disregard that one. Cosine repeats itself every 360 degrees to just keep adding or subtracting 360 to both of those answers and see if you get anything else in the range.


i see thanks
Because there will be more than one solution for that identity, for instance, sin x = 0.6 could exist as 36.86, but at that same point it could be 143.13, it's best to graph it on a sin graph, and by pinpointing the approximate location of 0.6 on the y axis, you will see that there is more than one point on the x axis where it exists.
Original post by AryanGh
Because there will be more than one solution for that identity, for instance, sin x = 0.6 could exist as 36.86, but at that same point it could be 143.13, it's best to graph it on a sin graph, and by pinpointing the approximate location of 0.6 on the y axis, you will see that there is more than one point on the x axis where it exists.


I see thanks bro xD

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