#circular measure(or whatever it's called. circles and sector thing)
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Alright before we solve that problem, I want you to solve this problem (it has something that we are gonna use when solving your problem)
Thanks
Ok let’s start solving by drawing this line (or let’s say connecting those two points)
What do you think the angles green and red are? 🤔
45° because it's a right angled triangle and since it's sides are radiuses they're equal making the angles equal
Yes! Exactly
Now how can we find the radius of the circle with the center Q? (note that we can also call the circle with center Q as C(Q,R))
We know the two sides(opposite and adjacent) are 5cm and it's a right angled triangle so we can use Pythagoras theorem to get side R
Exactly! and so what would be the length of the radius?
7.071067812cm
7.07cm
Yep!
let’s just use 5sqrt(2) for now because it’s easier
Now let’s move on to the important part of the solution, areas 👻
Do you agree with the thing shown in the picture?
section A is the answer
section B is the whole semi-circle
section C is that weird looking part
Ok nice
I’m sure you can easily find the area of the semi-circle
but the other one (section C) is a little harder
so let’s focus on that part
Yeah
Okay
Ok now tell me whatever you think about the way of finding the area of this shape?
(If you don’t have any ideas, think about separating the shape into two parts)
Finding the area of sector POQ seems easy enough but when it comes to POM I'm blank
yes!! That’s exactly what we want to do
so POQ is easy for you which is nice
but what’s interesting about this problem
is that for finding the area of POM, we again have to do separating xD
Oh okay
take a look at this picture, can you guess what we wanna do to find the area of POM?
Ohhh i think I see it
PQM is a sector so we find the area of that then theres a triangle(POQ) inside which we can also find the area of so we subtract the area of the triangle from the area of the sector to get the area of POM
EXACTLYY!11! 🔥
Now try to find the area and tell me the value
(use square root and pi btw I don’t wanna use irrational stuff 💀)
I mean not for example 5.432 xD
ok yeah go on
Okay so the area of the sector is
A = ⅛ pi × 49.9849 cm²
Triangle area = 12½ cm²
Area of POM = 6.2481pi - 12.5
I'm a bit confused on what you mean by square roots so sorry if I didn't I made a mistake in how I brought out the answer
your answer is completely correct!
the reason I’m telling you to keep the length like 5sqrt(2)
is because when you wanna for example fine the area of the circle
It would be:
5sqrt(2) * 5sqrt(2) = 25 times 2 = 50
instead of 49.989
But still
It’s alright for now since you are allowed to use calculators!
Oh I see
Oh I know see how to find the area of the shaded region thank you so much you've helped alot
You are welcome!
also I thank you for being here and actually thinking on the problem!
cya later mate 👋
Np its easier when I'm walked through the problem rather than just given an answer
Please don’t forget to close the forum 😅