Inverse trig functions

So in class my teacher brushed passed the topic without really explaining anything. Im doing EDEXCEL exam board for a level maths and there seems to be discrepancies on the importance of the topic. What from the topic (6.5) do I actually need to know and the depth of the questions Id be asked in the exam. Any help would be appreciated. Reading this back it seems silly but genuinely not sure.

Have you looked at something like the tlmaths videos on the topic (hes aqa but its very similar) or drfrost or ... or your textbook?

I have had a look at the textbook and also Biden maths who does edexcel he said it wasn’t important and TL maths I can’t find a video on it. However I tried doing Madasmaths questions on it and the maths was stuff I could do but just seemed overly challenging for a level and when I put it into AI it said it wasn’t something I’d be asked. I know I’m probably not making sense but it just seems such an odd thing.

Cant say this is 100% syllabus (but you can look that up on the spec) so tlmaths
https://sites.google.com/view/tlmaths/home/a-level-maths/full-a-level/e-trigonometry/e4-further-trigonometry
is all about the domain / range for arccos, arcsin, arctan and you should know those and how they relate to the usual sin/cos/tan curves / cast quadrant and why theyre defined like that for inverse functions. You might think how sqrt(x) is the inverse of x^2 and what range/domain restrictions there are. Similarly, you might think about their sketches and how theyre the inverse/reflection in the line y=x of the normal sin/cos/tan functions.
They (arctrig) crops up in calculus. You also have seemingly simple (but fiddly) questions based on things like sin(arccox(x)) and mapping it to a unit right triangle etc.
Not sure what more you want? Saying theyre odd (may have misinterpreted what you mean) is similar to saying sqrt() is odd, whereas undestand the domain/range restrictions, how its the inverse of x^2, what the sketch is, .... is important.

The calc part has been removed from the spec. Everything in what you said I know it’s the proof questions is where I see a grey area. Anyway thank you none the less

From a quick check, it looks like the calculus arctrig stuff is in further maths.

Yes I’m pretty it’s in fm but defiently not normal a level maths

From a quick check, it looks like the calculus arctrig stuff is in further maths.
Not sure what you mean about the proof questions / grey area?

Go on madasmaghs inverse trig questions. The proof questions there is what I’m talking about

wbf im about to turn in. Can you post an example question?
If not, ...

wbf im about to turn in. Can you post an example question?
If not, ...

On my phone so I can’t put a picture in

Thats fine. A few hints, it helps to think about it to draw a right triangle. So as its
arctan(x)
then you can represent that as a right triangle with opp x and base 1 and hypotenuse sqrt(1+x^2) using pythagoras.
Then its a double angle "2" and read off the side ratio corresponding to sin. So
sin(2theta) = 2sin(theta)cos(theta) = 2 * x/sqrt(1+x^2) * 1/sqrt(1+x^2)
personally I think sketching the right unit triangle is key and as its arctan, the unit part is the base of unit length.

Thank you, really Appreciate you bearing with me

Think it was the bear who was bearing with you.