Im having an issue of when to use Cos and Sin.(adsbygoogle = window.adsbygoogle || []).push({});

When calculating Force (Normal and Frictional) with multiple demension problems you are typically given the angle of the incline.

When trying to calculate for Fgx (or basically x) I would think to use cos(theta) and when dealing with Fgy (or basically y) I would think to use sin(theta).

Problem is my trig is 13 years rusty, and I really only need to know enough to work with these physics problems. Where I thought the above was correct, the text book had two examples and x and y in one question was calculated using cos and sin (for x and y respectively) and then the other question sin and cose where used to solve for (x and y).

Its throwing me through hoops now (maybe the difference was the shape of the triangle).

Any direction or help is greatly appreciated.

Thanks

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# Homework Help: Help with Cos and Sin

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