Trigometry (1 Viewer)

[Ranger Stacie]

How do you find angles using the cosine rule?

I do it by the formula, but most of the time it comes up saying syn error. What am I doing wrong? Its really pissing me off!!!!

I also am really crap with figuring out bearings...and I can tell if I understood it it would be easy

 

[0o0]

well if u could post the question, ill see where the mistake is.

 

[Ranger Stacie]

I have this problem with any triangle question that involves finding an angle with the cosine rule!

 

[0o0]

hmmm, i maybe u should use (brackets)

 

[hipsta_jess]

try doing it bit by bit, rather than plugging it all in at once. it takes a bit longer, but if you get the right answer, surely it is worth the marks..

 

[honky tonk]

This is assuming you are using a CASIO calculator:

Enter it into the calculator as so:

( a + b - c ) ( 2 x a x b )

Then, find the square root of your answer using the √ button on your calculator.

With that, select the SHIFT key, and then press your COS button, followed by the equals (=) sign.

After that, you should be able to press the Degrees/Minutes button, and turn your decimal into degrees.

Note: With the above formula, make sure that c is the side opposite to the angle you are trying to find, or else the formula will not work.

I hope this helps, let us know how you go.

 

[Ranger Stacie]

Thanks a lot for your help, i was away from school during that section of work