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2019 Edexcel IAL October Maths C12 unofficial answer

Sequence question:
p=31
q=-5
Sum=-1475

Area R question:
f(x)=(x-2)(x+2)(x+3)
Area R = 32 ( Area above the x-axis)

Trig angle question:
Obtuse angle = 138.2(if I remember correctly :biggrin:)
Missing angle= 180-138.2-30=11.8
x=4.04
AC=4.96 ( my memory may be wrong )

Circle question:
Centre (3,7)
Range of k: 49<=k<58

Trig identities:
ii)0.201, 2.940

Logo question:
Area=135pi
Perimeter = 23pi + 12

Sequence question: Colony of ants
p=3.51(%)
N=37

Tank question:
r = (15/4pi)^ 1/3
Area = (forgot)
h=0 for minimum value of A
(edited 4 years ago)
What was the range of values of k of the circle question?
You had to say that the redius is smaller than 3
What was the obtuse angle??
Reply 4
Original post by Ahmedayman
What was the obtuse angle??

138 approx
Reply 5
Original post by Teddy_Luz
Trig angle question:
Obtuse angle = 138.1(if I remember correctly :biggrin:)
then 11.8 (maybe)

Circle question:
Centre (3,7)
Range of k: 49<=k<58

Trig identities:
ii)0.201, 2.940

Logo question:
Area=135pi
Perimeter = 23pi + 12

Sequence question: Colony of ants
p=3.51(%)
N=37

Tank question:
r = (15/4pi)^ 1/3
Area = (forgot)
h=0 for minimum value of A


okay so my brother and i did the exam and out obtuse angle value was the same "108.1" for others, honestly i dread sharing my answers like if they turn out to be wrong i might basically go into depression for like no reason at all because we cant really do anything now whats coming is coming unless God changes it for us (hopefully)
Original post by Teddy_Luz
Tank question:
r = (15/4pi)^ 1/3
Area = (forgot)
h=0 for minimum value of A


r = (12/8pi)^(1/3)
Reply 7
Original post by CuriosityYay
r = (12/8pi)^(1/3)

Check if your value can make h become 0
Reply 8
Original post by Zeeeda
okay so my brother and i did the exam and out obtuse angle value was the same "108.1" for others, honestly i dread sharing my answers like if they turn out to be wrong i might basically go into depression for like no reason at all because we cant really do anything now whats coming is coming unless God changes it for us (hopefully)

If I remember clearly, the question said sin x =2/3, then x=sin^-1(2/3)= 41.8( acute, rejected), 138.2 (obtuse, accepted)
Original post by Teddy_Luz
If I remember clearly, the question said sin x =2/3, then x=sin^-1(2/3)= 41.8( acute, rejected), 138.2 (obtuse, accepted)

138.2?
But you were given an angle that said 30 degrees. So if you add 30 degrees + 41.8 the other angle has to be 108,2
No because he said to you that this angle is obtuse sk u had to do 180-41.8 which gives 138.2 to get the missing angle u should do 180-(30 138.2) which gives 11.8.
Original post by Teddy_Luz
Check if your value can make h become 0

I don't remember: h = what in terms of r

But h was equal to zero.
Reply 12
Original post by Ahmedayman
No because he said to you that this angle is obtuse sk u had to do 180-41.8 which gives 138.2 to get the missing angle u should do 180-(30 138.2) which gives 11.8.

we already had the other two angles, adding them up and subtracting that from 180 gave 108.1
Reply 13
Original post by Zeeeda
we already had the other two angles, adding them up and subtracting that from 180 gave

Sin x=2/3, x= 41.8, 180-30-41.8=108.2
That’s your process, right?
But what the question asked for is the obtuse, and the diagram also show the corresponding angle is clearly an obtuse. Obviously, 41.8 isn’t an obtuse, so u need to convert 41.8 into 138.2 first rather than input 41.8 directly. Then the missing angle=180-30-138.2=11.8
are you sure of N=37 not 39?
Original post by Teddy_Luz
Sequence question:
p=31
q=-5
Sum=-1475

Area R question:
f(x)=(x-2)(x+2)(x+3)
Area R = 32 ( Area above the x-axis)

Trig angle question:
Obtuse angle = 138.2(if I remember correctly :biggrin:)
Missing angle= 180-138.2-30=11.8
x=4.04
AC=4.96 ( my memory may be wrong )

Circle question:
Centre (3,7)
Range of k: 49<=k<58

Trig identities:
ii)0.201, 2.940

Logo question:
Area=135pi
Perimeter = 23pi + 12

Sequence question: Colony of ants
p=3.51(%)
N=37

Tank question:
r = (15/4pi)^ 1/3
Area = (forgot)
h=0 for minimum value of A

Hey , are you sure that the p is 3.51% and n=37, i got p 15/14 and n=20, if i remember correctly the question said after 2 years , this is where we both got different answers, as you assumed that its 2 years AFTER the start , hence n=3 and I assumed that it was from the beginning and got n=2 , so i would really appreciate it if you can tell me if I was right or wrong.
did people get 14.14 for surface area?
yea, 14.1
Reply 18
Original post by Teddy_Luz
Sin x=2/3, x= 41.8, 180-30-41.8=108.2
That’s your process, right?
But what the question asked for is the obtuse, and the diagram also show the corresponding angle is clearly an obtuse. Obviously, 41.8 isn’t an obtuse, so u need to convert 41.8 into 138.2 first rather than input 41.8 directly. Then the missing angle=180-30-138.2=11.8


but thry were asking about the obtuse angle itself, if the answer is 11.8 how can the angle be obtuse, obtuse angles are more than 90 and less than 180 in this case even if 108.19 isnt correct neither is 11.8.
Anyways the main thing right now is that we must score good, I hope God changes all our Answers to correct ones

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