Gcse maths

[ENAHGY]

Edexcel BLESSED the paper today
Genuinly think u got 80/80 and it wasn't even hard. Finished with time to spare I was js playing on my calc the whole hour.
Maybe the 9 is back in sight

 

[crn]

CCEA are niggers

Non-calculator section of our second paper was sooooo easy
calculator part was the hardest questions i had ever seen

and it's not just me rgonna kms for these grade boundaries

thankfully that was my last exam, still on study leave so im just rotting on here

 

[hatе]

calc is short for calculator btw

 

[discord m0d]

why is this in other languages?

 

[ENAHGY]

why is this in other languages?

Missclick

 

[yyk117]

all this to get brutally raped in sixth form

 

[Jesus_ist_König]

Does anyone know about the Taylor series?

 

[Jason5000]

Does anyone know about the Taylor series?

I used to know it but now i forgot it

 

[Jesus_ist_König]

I used to know it but now i forgot it

It interests me but then I go from topic to topic and never fucking finish!!!

I wanted to know how to derive sinus. Like you need to imagine that you have a fucking triangle with a 90 degree angle thingy. How the fuck do you go from that to creating sinus, cosinus and tangens????

I havent read anything about the taylor series. All i know is that its just a polynom to approximately copy another function and its used to get to sinus


but how did ppl find out about sinus??

 

[SaiNaz]

Edexcel BLESSED the paper today
Genuinly think u got 80/80 and it wasn't even hard. Finished with time to spare I was js playing on my calc the whole hour.
Maybe the 9 is back in sight

imma take edexecl math next year what do u use to study

 

[808AmnesiaLuver]

Edexcel BLESSED the paper today
Genuinly think u got 80/80 and it wasn't even hard. Finished with time to spare I was js playing on my calc the whole hour.
Maybe the 9 is back in sight

are you in igcse?

 

[abr0812]

anyone writing sat here

 

[ENAHGY]

are you in igcse?

No edexcel higher regular gcse

 

[ENAHGY]

imma take edexecl math next year what do u use to study

Tbh I don't study much, but I would just spam practice questions and do lots of past papers. If ur doing higher also try look at gcse hardest questions and try see how you would answer those

 

[SaiNaz]

Tbh I don't study much, but I would just spam practice questions and do lots of past papers. If ur doing higher also try look at gcse hardest questions and try see how you would answer those

i have exams starting 9th and i havent studied anything im lowkey kinda cooked and its hard for me to focus on doing past papers any tips?

 

[ENAHGY]

i have exams starting 9th and i havent studied anything im lowkey kinda cooked and its hard for me to focus on doing past papers any tips?

Find someone like a friend and js do it with them and boost ur ego by doing so much better than them.
Js like do the same paper and try to finish earlier while also getting a higher %
Competing against someone just makes it sm easier to lock in
Also short term, confidence it all that matters, if u come into an exam stressed and worried you probably will perform slightly worse than if ur optimistic and full of confidence

 

[2-CB]

Edexcel BLESSED the paper today
Genuinly think u got 80/80 and it wasn't even hard. Finished with time to spare I was js playing on my calc the whole hour.
Maybe the 9 is back in sight

GCSE maths was the easiest ever
I finished all the exams in like 45 then ldared for the rest of the time and got 8s

 

[Algernon]

It interests me but then I go from topic to topic and never fucking finish!!!

I wanted to know how to derive sinus. Like you need to imagine that you have a fucking triangle with a 90 degree angle thingy. How the fuck do you go from that to creating sinus, cosinus and tangens????

I havent read anything about the taylor series. All i know is that its just a polynom to approximately copy another function and its used to get to sinus


but how did ppl find out about sinus??

sin was created as triangles first, then people extended it for different angles getting the sin function, people matched the height to the angle experimentally and made the function as it repeats

taylor series is derived by integration by parts using fundamental theorem of calculus

f(x)=f(a)+int(a,x)(f'(t))dt, u=f', dv=dt, integration by parts gives uv-int(vdu), so f'(t)•t, int(f''(t)•t)dt -> f''(t)•t^2/2+int(f'''(t)•t^2/2) -> f'''(t)t^3/6 ...

as it extends out to infinity you get f(x)=f(a)+f'(a)t+f''(a)t^2/2+f'''(a)t^3/6...
substitute t=x-a from bounds of the integral, you get the taylor series

 

[Jesus_ist_König]

sin was created as triangles first, then people extended it for different angles getting the sin function, people matched the height to the angle experimentally and made the function as it repeats

taylor series is derived by integration by parts using fundamental theorem of calculus

f(x)=f(a)+int(a,x)(f'(t))dt, u=f', dv=dt, integration by parts gives uv-int(vdu), so f'(t)•t, int(f''(t)•t)dt -> f''(t)•t^2/2+int(f'''(t)•t^2/2) -> f'''(t)t^3/6 ...

as it extends out to infinity you get f(x)=f(a)+f'(a)t+f''(a)t^2/2+f'''(a)t^3/6...
substitute t=x-a from bounds of the integral, you get the taylor series

get more into detail about the sinus stuff how exactly?

 

[Algernon]

get more into detail about the sinus stuff how exactly?

sin is defined as the ratio of the opposite leg of a triangle divided by the hypotenuse the longest side

people found out that this ratio doesn't change no matter how big the triangle, (the hypotenuse would represent the radius)

so sin(x) was defined where sin(x) is the height ratio to longest side (when equal to 1, it is exactly the height), x is the angle (usually written theta to avoid confusion)

since it doesn't matter and will always be the same, they assumed the radius was 1 so they wouldn't have to divide

then they just manually recorded the height, they measured the angle then measured the height and got a list of sine values

since it repeats every rotation, they only had to do this for angles 0-360 degrees / 0-2pi radians and then repeat the values every rotation

 

[Jesus_ist_König]

sin is defined as the ratio of the opposite leg of a triangle divided by the hypotenuse the longest side

people found out that this ratio doesn't change no matter how big the triangle,

i dont get it if i do the deviding from the opposite leg with the hypotenuse in different triangles, I always get a different ratio?

(the hypotenuse would represent the radius)

No, thaless theroem. The hypotenuse is two times the radius

so sin(x) was defined where sin(x) is the height (length of the opposite), x is the angle (usually written theta to avoid confusion)

since it doesn't matter and will always be the same, they assumed the radius was 1 so they wouldn't have to divide

show this at 2 different triangles??

then they just manually recorded the height, they measured the angle then measured the height and got a list of sine values

since it repeats every rotation, they only had to do this for angles 0-360 degrees / 0-2pi radians and then repeat the values every rotation

 

[Algernon]

i dont get it if i do the deviding from the opposite leg with the hypotenuse in different triangles, I always get a different ratio?

are the angles the same?

No, thaless theroem. The hypotenuse is two times the radius

thales theorem is for a triangle inscribed a circle (meaning the triangle hits both ends, so its hypotenuse will be the diameter)

photo of thales theorem

photo of sine cosine triangle inside circle

this triangle starts at 0,0 though, so it is different

show this at 2 different triangles??

triangle

www.desmos.com

change the angle and A (radius), you will see the sine value remains the same

 

[Jesus_ist_König]

are the angles the same?

thales theorem is for a triangle inscribed a circle (meaning the triangle hits both ends, so its hypotenuse will be the diameter)

this triangle starts at 0,0 though, so it is different

triangle

www.desmos.com

change the angle and A (radius), you will see the sine value remains the same

yeah well shit bro if the angle stays the same then obviously strahlensatz but yeah okay i still dont get it how they came up with it

 

[Algernon]

yeah well shit bro if the angle stays the same then obviously strahlensatz but yeah okay i still dont get it how they came up with it

came up with what?

the values?
if you have a ruler, draw a point on a paper, measure 1 inch (you choose 1 since thats when opposite/hypotenuse=height, since hypotenuse=radius=1 in the circle) out from the point, then rotate it around, you have a circle of one now

now write a coordinate grid (flat line in both directions)

if you have a protractor, you should have an angle from the x axis, choose any angle then write out a line from the center point to the edge, measure the distance between the x axis and the angle, you now have a height value, this is your experimental sine value for the angle

they repeated this on almost every point on the circle, recorded it

then you have a table

x	sin(x)
numbers	numbers

you can repeat this every rotation, now you have sine values

 

[Jesus_ist_König]

came up with what?

the values?
if you have a ruler, draw a point on a paper, measure 1 inch (you choose 1 since thats when opposite/hypotenuse=height, since hypotenuse=radius=1 in the circle) out from the point, then rotate it around, you have a circle of one now

now write a coordinate grid (flat line in both directions)

if you have a protractor, you should have an angle from the x axis, choose any angle then write out a line from the center point to the edge, measure the distance between the x axis and the angle, you now have a height value, this is your experimental sine value for the angle

they repeated this on almost every point on the circle, recorded it

then you have a table

x	sin(x)
numbers	numbers

you can repeat this every rotation, now you have sine values

okay no i dont like this anymore iw wait laer i fwil come abkc but nwird hrig i want so do smth else