# General Thoughts: Mathematics (1 Viewer)

#### WileyWanimal

##### Member
Is someone going to upload some solutions??

#### yma

##### Member
I got a concave down parabola with TP at 1 and roots at -2 and 3.
Don't know if that's right though. :s
You're probably right.. I got 2 upward concave in my graph.. my graph looks very weird

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#### WileyWanimal

##### Member
minimum s.p. at (-2,0) , max at (1, ...) and cuts x-axis at x = 3
well you have SPs where f'(x)=0, so surely the derivitive graph=0 where there were SPs on the original graph... Doesn't it?

idk, now I'm doubting myself.

#### zeroni

##### New Member
any estimates for band 5? lel

#### zeroni

##### New Member
ah okay, cheers. Hopefully I'm not *too* fucked

#### Chocolatebubble

##### Active Member
~65 cut off maybe
I think the exam was a little easier (compared to 2013), wouldn't it be higher?

#### enigma_1

##### ~~~~ Miss Cricket ~~~~
I think the exam was a little easier (compared to 2013), wouldn't it be higher?
The maybe high 60s, definitely not in the 70s for the cut off though

#### orcevalm

##### Member
can anyone (if bothered) post the answers up for the MC ? i hope i got them right :/

#### chrisdelinet

##### Member
well you have SPs where f'(x)=0, so surely the derivitive graph=0 where there were SPs on the original graph... Doesn't it?

idk, now I'm doubting myself.
A is horizontal pt of inflexion, therefore at A, y' = 0 (reason why it touches x-axis) but values to the left and right of A will not change the sign of y' (we can see that y' > 0 for A < x and x> A). therefore the reason for a minimum at A

B is a pt of inflexion, meaning that y'' = 0 which means a maximum above the x - axis as y' > 0 for B < x and x > B.

lastly because there is a maximum at C, i'll cut the x-axis from above as y' > 0 for C < x and y' < 0 for x > C

therefore shape of derivative graph is \/\

#### hi im trash

##### Member
can anyone (if bothered) post the answers up for the MC ? i hope i got them right :/
i think theres a thread about MCQs already, could try looking there

what was the band 6 cut off for last year and the year before that? :S

#### Technoash

##### Member
can anyone (if bothered) post the answers up for the MC ? i hope i got them right :/
These are all from memory. Im not working any out again lol

1. A
2. B
3. D
4. C
5. B (i think)
6. D
7. B
8. A or D (the answer is B or C lol i fkd up)
9. A
10. A

Did I mess up anywhere?

#### chrisdelinet

##### Member
These are all from memory. Im not working any out again lol

1. A
2. B
3. D
4. C
5. B (i think)
6. D
7. B
8. A or D (the answer is B or C lol i fkd up)
9. A
10. A

Did I mess up anywhere?
i believe 8 is supposed to be C and 10 is D

#### nexusbrah

##### Harvey Specter of IB
These are all from memory. Im not working any out again lol

1. A
2. B
3. D
4. C
5. B (i think)
6. D
7. B
8. A or D (the answer is B or C lol i fkd up)
9. A
10. A

Did I mess up anywhere?
First one is B. 99% sure

#### trungduong12

##### Active Member
First one is B. 99% sure
Isnt it 5 is D?

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#### WileyWanimal

##### Member
A is horizontal pt of inflexion, therefore at A, y' = 0 (reason why it touches x-axis) but values to the left and right of A will not change the sign of y' (we can see that y' > 0 for A < x and x> A). therefore the reason for a minimum at A

B is a pt of inflexion, meaning that y'' = 0 which means a maximum above the x - axis as y' > 0 for B < x and x > B.

lastly because there is a maximum at C, i'll cut the x-axis from above as y' > 0 for C < x and y' < 0 for x > C

therefore shape of derivative graph is \/\
;( Yes, you're right...
Would I get 2/3 because I had it right at B and C, and I at least knew it touched the axis at A?

#### chrisdelinet

##### Member
Isnt it 5 is D?

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no mate, that'll give both equations positive gradients therefore can't be perpendicular to each other

#### phcan

##### New Member
Omg same here i think i left like 20 marks worth of questions fml

#### trungduong12

##### Active Member
no mate, that'll give both equations positive gradients therefore can't be perpendicular to each other
I wanna cry T_T
Forgot it says perpendicular

!!!!

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