Non Right angled Trigonometry, the Sine and Cosine rules.

Using the sine and cosine rules in non right angled triangles to find the missing sides and angles, and a brief look at the ambiguity in the Sine rule.

[@mmed_q_]

Nice video, explained it better than my professor.

[@randomcreator7555]

Thank you so much for this excellent teaching ❤🥹

[@conradstottsmith1550]

Hi Bob, thank you very much for the video. I was just wondering why when rearranging the equation for finding the largest angle it is all divided by 2bc.

[@CarmelitaGimots]

How did you end up with 40sin40 on 3?

[@wilsonlulamba7412]

Thank you, so much for sharing your knowledge, I have understood now....😍👌👌... Good teaching

[@siegventer1696]

Thank you this helps a lot 😁

[@theolawson]

11:00 (ignore, just where I am up to on the video so when I come back it’s easy to find) 👍

[@x0150]

did u ever come back to it 😿

[@mrfrag718]

@@x0150 I guess we'll never know 😂

[@LaytonGB]

Thank you for the video, helped me grasp this topic much better.

[@DvineVlogs]

14:47 isn’t the answer 20.35

[@KarsonT216]

No

[@endurofordaboys1768]

cheers bob

[@oblyth8450]

great video has helped me a lot

[@anyavilks5875]

what if i am only given one angle and one measurment

[@isqr8446]

i dont think you use like sine or cos rule if your triangle is Right angle

[@manban2457]

8 months late but if you have a right triangle you use trigonometry to find the missing side if you are given theta. But I don't think you can solve a 1 side and 1 angle non right triangle

[@deadagain9272]

Legend

[@徐子軒-g7z]

I use it to do my hw XD(I am form 2 now and I havent learnt this rules before)

[@armorvestrus4119]

When he got to 15 my brain over heated and melted down. LOL

[@galactafrog8318]

Thanks, I think you just saved my homework

[@carlojamesbracino718]

HELP! Why in my calculator in cosine rule; no. 1 ans is 10.62 and no. 2 ans 94.95? What did I do wrong?

[@carlojamesbracino718]

Ow I know now, I used the RAD not the DEG. That is why I have a different answer. Hahaha

[@mathswithbob]

Hi Carlo, glad to see you worked it out, a good reminder to check mode. Bob

[@bulistik5039]

Ok alright ok alright uh ok

[@XylaDemi]

thank you mathswithbob

[@22atmani]

thanks bob

[@CJM527]

Thanks sir

[@user-yh6dq2hl2t]

Thanks bro

[@archieprentice918]

when using the sine rule, why is my answer negative?

[@mathswithbob]

Hi Archie, with the sine rule, there is an ambiguity in that if sin☆=0.5 then ☆ can be 30 or 150 degrees, ( the geometry should suggset if the angle is obtuse ) some calculators give -30 degrees instead of 150 degrees, easy solution add 180 degrees and bingo hopefully you have the correct obtuse angle.

[@jajomlat]

thanks @mathswithbob