!! Maths HL Paper 2 2016 - Before and After

bookworm20

Jane98 wrote: »

i got 13/120 whic is approx. 01

Yea I got that too

Seaaan

bookworm20 wrote: »

q5a ii) anyone rember their answers, it was the one about the arrows and finding the probability that they will win

Something around .1 is what I got, I got probability of each possible way to win and added them

Seaaan

Jane98 wrote: »

i got 13/120 whic is approx. 01

Yeh I had that and wrote decimal too

DublinArnie

Ahhhh ****, realised I made a stupid mistake with the lantern area by halving the Base length .

DownOneTourist

DublinArnie wrote: »

Ahhhh ****, realised I made a stupid mistake with the lantern area by halving the Base length .

thats right though. 2(1/2B(H))+2(1/2B(H)) theres 2 of each type of triangle

Jane98

InTheNight wrote: »

Did anyone's answers for the circle have decimals? 7.xx and 11.xx?

yeah i got 7 and 7.****something

Jane98

bookworm20 wrote: »

To avoid debate here are some answers that im pretty sure are right but feel free to disagree:

orthrocentre: (7,6)
circle s: two solutins for centre one of them is 5,6 or 6,5 cant really remeber
triangle in semi cirlce: y=root x
venn diagram: x=0.15
angle |∠BCD| in roof lantern: 65
area of roof lantern: 15
Reason why The research institute took many large random samples of farm size: because the means would be normally distributed (i think
the value of n in last question: 494

Again feel free to disagree

how did u get centre of the circle?

DownOneTourist

i just tried to tot up my scores giving 4/10 attempt marks where i made a good attempt and over both papers i wound up with 89.5 percent. Really annoying! I wont have peace of mind until august. What if I gave myself too much? What if gave myself too little? Oh the feels!

Jane98

Papers up now!

malnurtured

DownOneTourist wrote: »

thats right though. 2(1/2B(H))+2(1/2B(H)) theres 2 of each type of triangle

2 types of triangle? What?

I just did 4 x (1/2BxH) ...?

BrownTrout

Seaaan wrote:

Also circle (x-7)^2 +(y-6)^2 = 25?

Yup

DublinArnie

malnurtured wrote: »

2 types of triangle? What?

I just did 4 x (1/2BxH) ...?

That's what I did but I recall getting 8m squared.

The question asked for the four triangles, maybe those who got 15 etc added the bottom aswell?

bookworm20

did anyone get the value of n in last question to be 494

DownOneTourist

malnurtured wrote: »

2 types of triangle? What?

I just did 4 x (1/2BxH) ...?

one triangle had base 3, the other had base 2.5, at least for me

malnurtured

DownOneTourist wrote: »

one triangle had base 3, the other had base 2.5, at least for me

God damn it. Yeah, that makes sense. Idiotic stuff on my part.

bookworm20

Jane98 wrote: »

how did u get centre of the circle?

It was simultaneous equations. Make the distance from the centre to the tangent equal to 5(the radius). Then sub in the equation of the line XC keeping in mind the absolute value brackets and u will get two values for x and two values for y (where x=-g and y=-f). Hope that helps

DublinArnie

bookworm20 wrote: »

It was simultaneous equations. Make the distance from the centre to the tangent equal to 5(the radius). Then sub in the equation of the line XC keeping in mind the absolute value brackets and u will get two values for x and two values for y (where x=-g and y=-f). Hope that helps

Wtf, I did all of that but instead of keeping absolute values, I squared both sides and then proceeded to do messy algebra.

So close....

Jane98

The centres are (6,7) and (-8,5)

bookworm20

bookworm20 wrote: »

did anyone get the value of n in last question to be 494

bump

randomlad727

bookworm20 wrote: »

bump

Yes I think I got that

Were we not supposed to get just one equation of the circle? I got one equation and could of got the second but I didn't bother

DownOneTourist

bookworm20 wrote: »

bump

a friend of mine did. You put 1 over root n equal to 0.045? Thats right i think. i screwed that up

wick___

What did anyone get for the construction..i just read root so I did the root 2 construction was a complete guess

Seaaan

Jane98 wrote: »

The centres are (6,7) and (-8,5)

I got 7,6 uhhhhhh

DownOneTourist

wick___ wrote: »

What did anyone get for the construction..i just read root so I did the root 2 construction was a complete guess

i bisected the line, drew a perpendicular, marked half of the line TU up the perpendicular with my compass, i joined this top point to an end of TU then I brought this point down to the original line. Anyone else do that?

DublinArnie

DownOneTourist wrote: »

i bisected the line, drew a perpendicular, marked half of the line TU up the perpendicular with my compass, i joined this top point to an end of TU then I brought this point down to the original line. Anyone else do that?

I literally used my ruler to measure TU and just drew a line that's root TU.

The question didn't say to use compass and straight edge?

luftmensch

DublinArnie wrote: »

I literally used my ruler to measure TU and just drew a line that's root TU.

The question didn't say to use compass and straight edge?

That's exactly what I did!

DownOneTourist

so to construct root2 you have two sides of 1... right? So to construct rootTU you have two sides of a half TU... right? Or am I misunderstanding?

DublinArnie

DownOneTourist wrote: »

so to construct root2 you have two sides of 1... right? So to construct rootTU you have two sides of a half TU... right? Or am I misunderstanding?

Ahhhh! You're 100% right.

That was a root 2 construction in disguise.

Gahv

DublinArnie wrote: »

Ahhhh! You're 100% right.

That was a root 2 construction in disguise.

I based it off the previous question, because it said y=root(x)

DownOneTourist

DublinArnie wrote: »

Ahhhh! You're 100% right.

That was a root 2 construction in disguise.

I'm not sure that I am tbh. it doesn't work with phythogoras!

Gahv

Also what did people get for the difference in tide heights 2nd last question for 8

bookworm20

Gahv wrote: »

Also what did people get for the difference in tide heights 2nd last question for 8

was that not 3?

Gahv

bookworm20 wrote: »

was that not 3?

Yeah that's what I said, but it seemed too easy

DublinArnie

Gahv wrote: »

Also what did people get for the difference in tide heights 2nd last question for 8

3.1 was highest and 0.1 was lowest, so 3m?

Gahv

DublinArnie wrote: »

3.1 was highest and 0.1 was lowest, so 3m?

Aight cool, I'm calculating my LC maths grade atm... No chill tbh fam

DublinArnie

Gahv wrote: »

Aight cool, I'm calculating my LC maths grade atm... No chill tbh fam

Same.

I need 2A1's, A2 (maths), and the rest C3+ to get my points.

iFergal

For the root TU line construction, I extended the line by one unit (cm in this case, as question stated), bisected that full line and drew a semi-circle. The perpendicular from U to the semi-circle was the required length.

The question seemed to hint at this, and this seems to back it up:

http://math.stackexchange.com/questions/705/compass-and-straightedge-construction-of-the-square-root-of-a-given-line

DownOneTourist

DublinArnie wrote: »

Same.

I need 2A1's, A2 (maths), and the rest C3+ to get my points.

youll get there arnie! Youve had your study guide since like september!

that's it fergal! Deffo! I was wondering why mine did not make a pythagorean triple... it's because I was wrong

Gahv

Keep it chill with all B2s

bookworm20

DownOneTourist wrote: »

youll get there arnie! Youve had your study guide since like september!

I need four A1s and Bs in the rest. Maths has to be one of my A1s. The rest are gonna be bio, physics,chem or applied maths

DownOneTourist

bookworm20 wrote: »

I need four A1s and Bs in the rest. Maths has to be one of my A1s. The rest are gonna be bio, physics,chem or applied maths

goog luck with that!;) I wish i was doing that well. I probably got an a2 in maths, hoping for an a1 in appmaths but all the others are low b's or c's

Gahv

bookworm20 wrote: »

I need four A1s and Bs in the rest. Maths has to be one of my A1s. The rest are gonna be bio, physics,chem or applied maths

We're all gonna make it lad

DublinArnie

bookworm20 wrote: »

I need four A1s and Bs in the rest. Maths has to be one of my A1s. The rest are gonna be bio, physics,chem or applied maths

Biology is definitely a doable A1.

bookworm20

DublinArnie wrote: »

Biology is definitely a doable A1.

yea i got one in the mocks shouldnt be too hard to do it again

adam240610

from my marking it looks like 287/300 for paper one and 255-265/300 for paper two

This is gonna make me very nervous come august... border between A1 and A2

Seaaan

Need 550, so far so good with math I think, we'll see how horrid biology goes tomorrow! Irish A1/physics A1/Chemistry A1/construction A1/French or biology B1 and we have a handy 600.. A man can dream right

Really hoping Irish bonus nets me the A2 in maths if I'm a few marks off..

bookworm20

does anyone actually know how to do the cot proof?

DublinArnie

bookworm20 wrote: »

does anyone actually know how to do the cot proof?

It was actually easy, did you try change the left side or right side?

I did the right side and got nowhere but before the exam finished I tried the left got it in seconds if you use the trig identifies in log book.

bookworm20

DublinArnie wrote: »

It was actually easy, did you try change the left side or right side?

I did the right side and got nowhere but before the exam finished I tried the left got it in seconds if you use the trig identifies in log book.

i tried the left side the entire time and got nowhere, which formula did u use?

DownOneTourist

bookworm20 wrote: »

i tried the left side the entire time and got nowhere, which formula did u use?

i used cosA+coB formula and sinA-sinB formulas i think