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  1. #1 angles 
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    hi guys. I want to ask how to move angles from one quadrant to another? see i have an angle -60 degree (in fourth quadrant) but in my question Y has a positive value while X is negative which means i have to have the angle in the second quadrant. help


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  3. #2  
    Forum Radioactive Isotope MagiMaster's Avatar
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    Angles only really make sense when you know where 0 degrees is (and which way around you're going). If you limit yourself to -60 degrees from an axis, that still leaves 8 possibilities. See if your problem doesn't state -60 from something.


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  4. #3  
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    Quote Originally Posted by MagiMaster View Post
    Angles only really make sense when you know where 0 degrees is (and which way around you're going). If you limit yourself to -60 degrees from an axis, that still leaves 8 possibilities. See if your problem doesn't state -60 from something.
    It just says -60 degrees
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  5. #4  
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    Without knowing the rest of the problem, I can't really offer any other advise. (One thing though is that we don't typically give homework answers here, but if you post what you've done so far, we can give advise.)

    Edit: There is a conventional coordinate system with +X to the right and +Y up, 0 degrees to the right and angles going counterclockwise (which means cos(a) gives X and sin(A) gives Y), but this just raises the problem mentioned in the OP.

    Edit again: Computer screens use X to the right and Y down, but I doubt that helps much.
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  6. #5  
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    Ok see the Que gives x=-(underroot 3)/2 and y=0.5 using tan-1(y/x) angle is -60 degrees
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  7. #6  
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    Well, just plugging those numbers in the calculator gives an angle of -30, but arctan is limited to two quadrants. But I don't actually see a question in what you wrote, so I'm still not sure what exactly's wrong.
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  8. #7  
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    according to the values of X and Y the angle must be in second quadrant but -30 lies in fourth quadrant. so how do i move it to second quadrant?
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  9. #8  
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    I still don't know what question you're trying to answer so I still can't really offer any advice. Can you post the full problem and what you've done on it so far?
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